add language learner project

Dutch and Korean (explained in English) and English (explained in Dutch)
from A1 to C1, with a Hangul level for Korean. Lessons with notes, words
and sentences generate multiple-choice, typing, sentence building, cloze,
listening and matching exercises. Endless challenges: a seeded daily
challenge, sprint, survival, mixed practice, level tests, spaced-repetition
reviews and generated drills (numbers, clock times, de/het, plurals, Dutch
and Korean conjugation, particles, Hangul reading, irregular verbs).
Progress is stored in localStorage with export/import.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -6,3 +6,29 @@ This is my personal website, including:
 - About me
 - Blog posts + comments
 - Projects like Animaldex, CatchEmAll
+
+## Language learner
+
+`/projects/language-learner` teaches Dutch and Korean (explained in English) and
+English (explained in Dutch), from A1 to C1. Korean starts with a Hangul level.
+It runs entirely in the browser: no database tables, migrations or API keys.
+
+- Course content lives in `src/lib/language-learner/courses/<lang>/<level>.ts` as
+  compact `target | translation | note` lines, plus markdown notes and
+  multiple-choice grammar questions (`prompt | answer | wrong; wrong | explanation`).
+  Exercises (choice, typing, sentence building, fill-in-the-blank, listening,
+  matching) are generated from that data. `content.test.ts` validates every lesson.
+- Endless drills are generated by code in `src/lib/language-learner/drills/`:
+  number words, Dutch/English clock times, de/het, plurals, Dutch and Korean
+  conjugation (a rule-based Korean conjugator handling the ㅂ/ㄷ/르/ㅅ/ㅎ
+  irregulars), Korean particles and counters, Hangul reading, English irregular
+  verbs, comparatives and a/an.
+- Challenges: a seeded daily challenge (first score of the day counts), 60-second
+  sprint, survival with three lives, mixed practice, level tests that mark a level
+  as done at 80%, and spaced-repetition reviews (simplified SM-2).
+- Audio uses the browser's speech synthesis, so listening exercises appear only
+  when the device has a voice for the language. Romanization of Korean is
+  approximate Revised Romanization.
+- Progress, streaks and settings are stored in `localStorage`
+  (`language-learner-v1`), per browser. Export/import on the overview page moves
+  them between devices.

eslint.config.js

@@ -20,7 +20,7 @@ export default [
 		}
 	},
 	{
-		files: ['**/*.svelte'],
+		files: ['**/*.svelte', '**/*.svelte.ts'],
 		languageOptions: {
 			parserOptions: {
 				parser: ts.parser

src/lib/language-learner/challenges.test.ts

@@ -0,0 +1,33 @@
+import { describe, expect, it } from 'vitest';
+import { mixed, scopeOf } from './challenges';
+import ko from './courses/ko';
+import { drills } from './drills/ko';
+import { seeded } from './random';
+
+describe('challenges', () => {
+	it('gives beginners enough to practise', () => {
+		const scope = scopeOf(ko, undefined);
+		expect(scope.lessons[0].id).toBe('ko-vowels');
+		expect(
+			scope.lessons.reduce((n, l) => n + l.words.length + l.sentences.length, 0)
+		).toBeGreaterThanOrEqual(15);
+	});
+
+	it('limits a scope to one level', () => {
+		const scope = scopeOf(ko, undefined, 'b1');
+		expect(scope.lessons.every((l) => l.level === 'b1')).toBe(true);
+		expect(scope.level).toBe(3);
+	});
+
+	it('keeps producing exercises', () => {
+		const next = mixed({
+			course: ko,
+			scope: scopeOf(ko, undefined, 'a2'),
+			drills,
+			rng: seeded(1),
+			opts: { typing: false, audio: false }
+		});
+		const keys = Array.from({ length: 200 }, () => next().key);
+		expect(new Set(keys).size).toBeGreaterThan(50);
+	});
+});

src/lib/language-learner/challenges.ts

@@ -0,0 +1,128 @@
+import { allLessons } from './course';
+import type { DrillMode } from './drills';
+import { fromDrill, reviewExercise, type ExerciseOptions } from './exercises';
+import type { LangProgress } from './progress.svelte';
+import { pick, shuffle, type Rng } from './random';
+import { strength } from './srs';
+import type { Course, Entry, Exercise, Lesson } from './types';
+
+/** CEFR level as a number for the endless drills: Hangul and A1 are 1, C1 is 5. */
+export function levelNumber(levelId: string): number {
+	return { hangul: 1, a1: 1, a2: 2, b1: 3, b2: 4, c1: 5 }[levelId] ?? 1;
+}
+
+export type Scope = { lessons: Lesson[]; level: number; label: string };
+
+/**
+ * What mixed challenges draw from. By default: completed lessons plus the next one,
+ * topped up in course order so beginners always have enough to practise.
+ */
+export function scopeOf(course: Course, p: LangProgress | undefined, scopeId = ''): Scope {
+	const lessons = allLessons(course);
+	if (scopeId === 'all') return { lessons, level: 5, label: 'Everything' };
+	const chosen = course.levels.find((lv) => lv.id === scopeId);
+	if (chosen)
+		return { lessons: chosen.lessons, level: levelNumber(chosen.id), label: `${chosen.band} only` };
+
+	const done = lessons.filter((l) => p?.lessons[l.id]);
+	const next = lessons.find((l) => !p?.lessons[l.id]);
+	const picked = new Set([...done, ...(next ? [next] : [])]);
+	for (const l of lessons) {
+		if ([...picked].reduce((n, x) => n + x.words.length + x.sentences.length, 0) >= 15) break;
+		picked.add(l);
+	}
+	const result = lessons.filter((l) => picked.has(l));
+	return {
+		lessons: result,
+		level: Math.max(1, ...result.map((l) => levelNumber(l.level))),
+		label: 'What I have learned'
+	};
+}
+
+type MixedOptions = {
+	course: Course;
+	scope: Scope;
+	drills: DrillMode[];
+	rng: Rng;
+	opts: ExerciseOptions;
+	p?: LangProgress;
+	/** Grows the drill level over time, for survival. */
+	ramp?: boolean;
+};
+
+/** An endless supply of mixed exercises: vocabulary, grammar questions and generated drills. */
+export function mixed({ course, scope, drills, rng, opts, p, ramp }: MixedOptions): () => Exercise {
+	const entries = scope.lessons.flatMap((l) => [...l.words, ...l.sentences]);
+	const grammar = scope.lessons.flatMap((l) => l.drills.map((d) => ({ d, id: l.id })));
+	const recent: string[] = [];
+	let count = 0;
+
+	const weightOf = (e: Entry) => 1 + (1 - strength(p?.cards[e.id])) * 3;
+	const total = entries.reduce((n, e) => n + weightOf(e), 0);
+	const weighted = () => {
+		let roll = rng() * total;
+		for (const e of entries) {
+			roll -= weightOf(e);
+			if (roll <= 0) return e;
+		}
+		return entries[entries.length - 1];
+	};
+
+	return () => {
+		count++;
+		for (let attempt = 0; attempt < 6; attempt++) {
+			const roll = rng();
+			let ex: Exercise;
+			if (roll < 0.6 || (!grammar.length && !drills.length)) {
+				const e = weighted();
+				ex = reviewExercise(e, entries, rng, opts, strength(p?.cards[e.id]));
+			} else if (roll < 0.82 && grammar.length) {
+				const g = pick(rng, grammar);
+				ex = fromDrill(g.d, g.id, rng);
+			} else if (drills.length) {
+				const level = ramp ? Math.min(5, scope.level + Math.floor(count / 15)) : scope.level;
+				ex = pick(rng, drills).make({ rng, level, opts, course });
+			} else continue;
+			if (!recent.includes(ex.key) || attempt === 5) {
+				recent.push(ex.key);
+				if (recent.length > 8) recent.shift();
+				return ex;
+			}
+		}
+		return reviewExercise(weighted(), entries, rng, opts);
+	};
+}
+
+/** Due cards first, then the weakest known cards, forever. */
+export function reviews(
+	course: Course,
+	p: LangProgress,
+	dueIds: string[],
+	rng: Rng,
+	opts: ExerciseOptions
+) {
+	const byId = new Map(
+		allLessons(course)
+			.flatMap((l) => [...l.words, ...l.sentences])
+			.map((e) => [e.id, e])
+	);
+	const pool = [...byId.values()];
+	const due = dueIds.map((id) => byId.get(id)).filter((e): e is Entry => !!e);
+	const known = Object.keys(p.cards)
+		.map((id) => byId.get(id))
+		.filter((e): e is Entry => !!e);
+	const queue = shuffle(rng, due).map((e) =>
+		reviewExercise(e, pool, rng, opts, strength(p.cards[e.id]))
+	);
+	let extra: Entry[] = [];
+	const more = () => {
+		if (!known.length) return null;
+		if (!extra.length)
+			extra = [...known]
+				.sort((a, b) => strength(p.cards[a.id]) - strength(p.cards[b.id]) || rng() - 0.5)
+				.slice(0, 25);
+		const e = extra.shift()!;
+		return reviewExercise(e, pool, rng, opts, strength(p.cards[e.id]));
+	};
+	return { queue, more, due: due.length, known: known.length };
+}

src/lib/language-learner/content.test.ts

@@ -0,0 +1,85 @@
+import { describe, expect, it } from 'vitest';
+import { allEntries, allLessons } from './course';
+import { lessonSession, reviewExercise } from './exercises';
+import { seeded } from './random';
+import { optionKey as normalize } from './text';
+import en from './courses/en';
+import ko from './courses/ko';
+import nl from './courses/nl';
+import { drills as nlDrills } from './drills/nl';
+import { drills as koDrills } from './drills/ko';
+import { drills as enDrills } from './drills/en';
+import type { Exercise } from './types';
+
+const courses = { nl, ko, en };
+const drillSets = { nl: nlDrills, ko: koDrills, en: enDrills };
+
+function checkExercise(ex: Exercise) {
+	if (ex.type === 'choose') {
+		expect(ex.options).toContain(ex.answer);
+		expect(
+			new Set(ex.options.map(normalize)).size,
+			`${ex.key}: duplicate options ${ex.options}`
+		).toBe(ex.options.length);
+		expect(ex.options.length).toBeGreaterThanOrEqual(2);
+		expect(ex.options.length, ex.key).toBeLessThanOrEqual(4);
+	}
+	if (ex.type === 'type') expect(ex.accept.length).toBeGreaterThan(0);
+	if (ex.type === 'build') expect(ex.tiles.length).toBeGreaterThan(0);
+	if (ex.type === 'match') {
+		expect(new Set(ex.pairs.map((p) => normalize(p.gloss))).size, ex.key).toBe(ex.pairs.length);
+		expect(new Set(ex.pairs.map((p) => normalize(p.target))).size, ex.key).toBe(ex.pairs.length);
+	}
+}
+
+describe.each(Object.entries(courses))('%s course', (code, course) => {
+	it('has unique lesson ids and content in every lesson', () => {
+		const ids = allLessons(course).map((l) => l.id);
+		expect(new Set(ids).size).toBe(ids.length);
+		for (const lesson of allLessons(course)) {
+			expect(lesson.words.length, lesson.id).toBeGreaterThanOrEqual(4);
+			const ids = [...lesson.words, ...lesson.sentences].map((e) => e.id);
+			expect(
+				ids.filter((id, i) => ids.indexOf(id) !== i),
+				lesson.id
+			).toEqual([]);
+			expect(lesson.notes.length, lesson.id).toBeGreaterThan(50);
+			for (const drill of lesson.drills) {
+				expect(drill.wrong.map(normalize), `${lesson.id}: ${drill.prompt}`).not.toContain(
+					normalize(drill.answer)
+				);
+				expect(new Set(drill.wrong.map(normalize)).size, `${lesson.id}: ${drill.prompt}`).toBe(
+					drill.wrong.length
+				);
+			}
+		}
+	});
+
+	it('generates valid lesson sessions', () => {
+		for (const lesson of allLessons(course))
+			for (const opts of [
+				{ typing: true, audio: true },
+				{ typing: false, audio: false }
+			]) {
+				const session = lessonSession(course, lesson, seeded(lesson.id), opts);
+				expect(session.length, lesson.id).toBeGreaterThan(lesson.words.length);
+				session.forEach(checkExercise);
+			}
+	});
+
+	it('generates review exercises for every entry', () => {
+		const pool = allEntries(course);
+		const rng = seeded(code);
+		for (const entry of pool)
+			checkExercise(reviewExercise(entry, pool, rng, { typing: true, audio: true }, rng()));
+	});
+
+	it('generates endless drills at every level', () => {
+		const rng = seeded(`drills-${code}`);
+		for (const drill of drillSets[code as keyof typeof drillSets])
+			for (let level = 1; level <= 5; level++)
+				for (let i = 0; i < 60; i++)
+					for (const typing of [true, false])
+						checkExercise(drill.make({ rng, level, opts: { typing, audio: true }, course }));
+	});
+});

src/lib/language-learner/course.ts

@@ -0,0 +1,111 @@
+import { normalize } from './text';
+import type { Course, Drill, Entry, EntryKind, LangCode, Lesson, Level } from './types';
+
+type LessonSource = {
+	id: string;
+	title: string;
+	summary: string;
+	notes?: string;
+	/** One per line: `target | gloss | note`. Separate alternatives with `;`. */
+	words?: string;
+	sentences?: string;
+	/** Hangul letters: `letter | romanization | note`. */
+	script?: string;
+	/** One per line: `prompt | answer | wrong; wrong; wrong | explanation`. */
+	drills?: string;
+};
+
+const lines = (source = '') =>
+	source
+		.split('\n')
+		.map((line) => line.trim())
+		.filter((line) => line && !line.startsWith('#'));
+
+const alternatives = (value: string) =>
+	value
+		.split(';')
+		.map((part) => part.trim())
+		.filter(Boolean);
+
+function entries(
+	source: string | undefined,
+	kind: EntryKind,
+	lesson: string,
+	code: LangCode
+): Entry[] {
+	return lines(source).map((line) => {
+		const [target, gloss, note] = line.split('|').map((part) => part.trim());
+		if (!target || !gloss) throw new Error(`Malformed ${kind} in ${code}/${lesson}: ${line}`);
+		const accepted = alternatives(target);
+		return {
+			id: `${code}:${kind[0]}:${normalize(accepted[0])}`,
+			kind,
+			target: accepted,
+			gloss: alternatives(gloss),
+			note: note || undefined,
+			lesson
+		};
+	});
+}
+
+function drills(source: string | undefined, lesson: string): Drill[] {
+	return lines(source).map((line) => {
+		const [prompt, answer, wrong, explain] = line.split('|').map((part) => part.trim());
+		if (!prompt || !answer || !wrong) throw new Error(`Malformed drill in ${lesson}: ${line}`);
+		return { prompt, answer, wrong: alternatives(wrong), explain: explain || undefined };
+	});
+}
+
+/** Strip the shared indentation of template literals so markdown renders correctly. */
+function dedent(text = ''): string {
+	const rows = text.replace(/^\n/, '').replace(/\s+$/, '').split('\n');
+	const indent = Math.min(...rows.filter((r) => r.trim()).map((r) => r.match(/^\s*/)![0].length));
+	return rows.map((r) => r.slice(Number.isFinite(indent) ? indent : 0)).join('\n');
+}
+
+export const lesson = (source: LessonSource) => source;
+
+export const level = (
+	id: string,
+	band: string,
+	title: string,
+	description: string,
+	lessons: LessonSource[]
+) => ({
+	id,
+	band,
+	title,
+	description,
+	lessons
+});
+
+export function course(meta: Omit<Course, 'levels'>, levels: ReturnType<typeof level>[]): Course {
+	return {
+		...meta,
+		levels: levels.map((lv): Level => ({
+			...lv,
+			lessons: lv.lessons.map((src): Lesson => ({
+				id: src.id,
+				title: src.title,
+				summary: src.summary,
+				notes: dedent(src.notes),
+				words: [
+					...entries(src.script, 'script', src.id, meta.code),
+					...entries(src.words, 'word', src.id, meta.code)
+				],
+				sentences: entries(src.sentences, 'sentence', src.id, meta.code),
+				drills: drills(src.drills, src.id),
+				level: lv.id
+			}))
+		}))
+	};
+}
+
+export const allLessons = (c: Course) => c.levels.flatMap((lv) => lv.lessons);
+
+export const allEntries = (c: Course) =>
+	allLessons(c).flatMap((ls) => [...ls.words, ...ls.sentences]);
+
+export function findLesson(c: Course, id: string) {
+	return allLessons(c).find((ls) => ls.id === id);
+}

src/lib/language-learner/courses/en/a1.ts

@@ -0,0 +1,567 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a1',
+	'A1',
+	'Beginner',
+	'Begroeten, jezelf voorstellen, getallen, familie en de present simple.',
+	[
+		lesson({
+			id: 'en-hello',
+			title: 'Hello!',
+			summary: 'Begroeten, bedanken en afscheid nemen',
+			notes: `
+			**Hi** en **hello** kun je altijd gebruiken. **Hey** is heel informeel.
+
+			| Engels | wanneer |
+			|---|---|
+			| Good morning | tot ongeveer 12:00 |
+			| Good afternoon | 12:00–18:00 |
+			| Good evening | 's avonds, als begroeting |
+			| Good night | alleen bij afscheid of slapengaan |
+
+			**How are you?** is vaak gewoon een begroeting. Antwoord kort: *Fine, thanks. And you?*
+
+			Let op: **please** is "alsjeblieft" bij een verzoek, maar als je iets aangeeft zeg je **here you are**.
+			"Graag gedaan" is **you're welcome** of **no problem**.
+		`,
+			words: `
+			hello; hi | hallo; hoi
+			goodbye; bye | tot ziens; doei
+			good morning | goedemorgen
+			good afternoon | goedemiddag
+			good evening | goedenavond
+			good night | welterusten; goedenacht
+			see you later | tot later
+			please | alsjeblieft (bij een verzoek)
+			here you are | alsjeblieft (bij het aangeven)
+			thank you; thanks | dank je wel; bedankt
+			you're welcome | graag gedaan
+			sorry | sorry
+			excuse me | pardon
+			yes | ja
+			no | nee
+		`,
+			sentences: `
+			Hi, how are you? | Hoi, hoe gaat het?
+			I'm fine, thanks. And you? | Goed, dank je. En met jou?
+			Nice to meet you. | Leuk je te ontmoeten.
+			See you tomorrow! | Tot morgen!
+			A coffee, please. | Een koffie, alsjeblieft.
+			Thank you very much. | Heel erg bedankt.
+			Excuse me, where is the station? | Pardon, waar is het station?
+		`,
+			drills: `
+			It is 21:00 and you arrive at a party: | Good evening | Good night; Good morning; Good afternoon | Good night zeg je alleen bij afscheid.
+			You give someone their coffee: | Here you are | Please; You're welcome; Thank you
+			Someone says "Thank you!" You answer: | You're welcome | Please; Here you are; Excuse me
+			Hoe gaat het? | How are you? | How do you go?; How goes it?; How is it going you?
+		`
+		}),
+		lesson({
+			id: 'en-to-be',
+			title: 'I am, you are',
+			summary: 'Persoonlijke voornaamwoorden en "to be"',
+			notes: `
+			| | to be | kort |
+			|---|---|---|
+			| I | am | I'm |
+			| you | are | you're |
+			| he / she / it | is | he's / she's / it's |
+			| we / you / they | are | we're / you're / they're |
+
+			**You** is zowel jij, u als jullie.
+
+			Ontkenning: **not** na de vorm van *be*: *I'm **not** tired. She **isn't** here.*
+			Vraag: zet *be* vooraan: ***Are** you Dutch? **Is** he a teacher?*
+
+			Let op: **ik ben 20** is ***I am 20*** (niet ~~I have 20~~), en **ik heb het koud** is ***I am cold***.
+			Een beroep krijgt altijd **a/an**: *I'm **a** student. She's **an** engineer.*
+		`,
+			words: `
+			I | ik
+			you | jij; u; jullie
+			he | hij
+			she | zij (enkelvoud)
+			it | het
+			we | wij
+			they | zij (meervoud)
+			am | ben
+			is | is
+			are | bent; zijn
+			name | naam
+			student | student
+			teacher | leraar; lerares
+			from | uit; van
+			Dutch | Nederlands; Nederlander
+		`,
+			sentences: `
+			My name is Emma. | Mijn naam is Emma.
+			I'm from the Netherlands. | Ik kom uit Nederland.
+			Are you a student? | Ben jij student?
+			She's a teacher. | Zij is lerares.
+			We aren't tired. | We zijn niet moe.
+			They're my friends. | Het zijn mijn vrienden.
+			I'm twenty years old. | Ik ben twintig jaar.
+			Is it cold outside? | Is het koud buiten?
+		`,
+			drills: `
+			She ___ from Amsterdam. | is | are; am; be
+			They ___ my parents. | are | is; am; be
+			I ___ a student. | am | is; are; be
+			Ik ben student: | I'm a student. | I'm student.; I have a student.; I'm the student. | Een beroep krijgt a/an.
+			Ik ben 30: | I'm 30. | I have 30.; I have 30 years.; I'm 30 years.
+			Heb je het koud? | Are you cold? | Do you have cold?; Have you cold?; Is you cold?
+		`
+		}),
+		lesson({
+			id: 'en-numbers',
+			title: 'One, two, three',
+			summary: 'Getallen, leeftijd en telefoonnummers',
+			notes: `
+			| | | | |
+			|---|---|---|---|
+			| 1 one | 6 six | 11 eleven | 16 sixteen |
+			| 2 two | 7 seven | 12 twelve | 17 seventeen |
+			| 3 three | 8 eight | 13 thirteen | 18 eighteen |
+			| 4 four | 9 nine | 14 fourteen | 19 nineteen |
+			| 5 five | 10 ten | 15 fifteen | 20 twenty |
+
+			Tientallen: twenty, thirty, **forty** (zonder u!), fifty, sixty, seventy, eighty, ninety.
+
+			In het Engels komen **tientallen eerst**, met een streepje: **twenty-one** (niet "one-and-twenty"), **forty-five**.
+
+			*-teen* en *-ty* klinken verschillend: thir**teen** (klemtoon achteraan) vs **thir**ty (klemtoon vooraan).
+
+			Telefoonnummers cijfer voor cijfer, 0 is **"oh"**: 06 = *oh six*. Twee dezelfde: *double four*.
+		`,
+			words: `
+			one | een
+			two | twee
+			three | drie
+			four | vier
+			five | vijf
+			eleven | elf
+			twelve | twaalf
+			thirteen | dertien
+			fifteen | vijftien
+			twenty | twintig
+			thirty | dertig
+			forty | veertig
+			fifty | vijftig
+			hundred | honderd
+			thousand | duizend
+			old | oud
+		`,
+			sentences: `
+			How old are you? | Hoe oud ben je?
+			I'm twenty-five. | Ik ben vijfentwintig.
+			What's your phone number? | Wat is je telefoonnummer?
+			It costs forty euros. | Het kost veertig euro.
+			I have two brothers. | Ik heb twee broers.
+			There are thirty students in my class. | Er zitten dertig leerlingen in mijn klas.
+		`,
+			drills: `
+			45 | forty-five | fourty-five; five-and-forty; fifty-four
+			14 | fourteen | forteen; fourty; forty
+			90 | ninety | ninty; nineteen; nineth
+			12 | twelve | twelf; twoteen; eleven
+			32 | thirty-two | two-and-thirty; thirteen-two; twenty-three
+		`
+		}),
+		lesson({
+			id: 'en-family',
+			title: 'My family',
+			summary: "Familie, bezittelijke voornaamwoorden en 's",
+			notes: `
+			### Bezittelijke voornaamwoorden
+			| | |
+			|---|---|
+			| my | mijn |
+			| your | jouw, uw, jullie |
+			| his | zijn |
+			| her | haar |
+			| its | zijn/haar (dingen, dieren) |
+			| our | ons, onze |
+			| their | hun |
+
+			### Bezit met 's
+			*Anna**'s** brother* — de broer van Anna. Meervoud op -s: alleen een apostrof: *my parents**'** house*.
+
+			**its** (bezit, zonder apostrof) ≠ **it's** (= it is).
+
+			### Have got
+			In Brits Engels zeg je vaak **have got** voor bezit: *I**'ve got** a sister. **Has** she **got** kids?* Beide zijn goed: *I have a sister.*
+		`,
+			words: `
+			family | familie; gezin
+			mother; mum | moeder; mama
+			father; dad | vader; papa
+			parents | ouders
+			sister | zus
+			brother | broer
+			son | zoon
+			daughter | dochter
+			child | kind
+			children | kinderen
+			husband | echtgenoot
+			wife | echtgenote
+			grandmother | oma
+			grandfather | opa
+			aunt | tante
+			uncle | oom
+			cousin | neef; nicht (kind van oom/tante)
+		`,
+			sentences: `
+			This is my mother. | Dit is mijn moeder.
+			I've got two sisters. | Ik heb twee zussen.
+			Have you got any children? | Heb jij kinderen?
+			Her husband is Scottish. | Haar man is Schots.
+			My brother's name is Tom. | De naam van mijn broer is Tom.
+			Our parents live in Utrecht. | Onze ouders wonen in Utrecht.
+			Their house is very big. | Hun huis is erg groot.
+		`,
+			drills: `
+			Dit is de auto van Mark: | This is Mark's car. | This is the car of Mark.; This is Marks car.; This is Mark car.
+			Is that ___ bag? (haar) | her | his; she; hers
+			The dog wants ___ food. | its | it's; his; it
+			Het huis van mijn ouders: | my parents' house | my parent's house; my parents house; the house from my parents
+			She ___ got a brother. | has | have; is; does
+		`
+		}),
+		lesson({
+			id: 'en-present-simple',
+			title: 'I work, she works',
+			summary: 'De present simple en de -s bij he/she/it',
+			notes: `
+			De **present simple** gebruik je voor gewoontes, feiten en dingen die altijd zo zijn.
+
+			| | work |
+			|---|---|
+			| I / you / we / they | work |
+			| **he / she / it** | work**s** |
+
+			Vergeet de **-s** niet! Spelling: *watch → watch**es**, go → go**es**, study → stud**ies**, have → **has***.
+
+			### Ontkenning en vraag met do / does
+			- *I **don't** work on Sundays. She **doesn't** work.*
+			- ***Do** you like coffee? **Does** he live here?*
+
+			Na **does/doesn't** geen -s meer: *Does she **work**?* (niet ~~works~~).
+
+			Nederlanders zeggen vaak ~~Work you here?~~ — in het Engels **altijd** met do/does: *Do you work here?*
+		`,
+			words: `
+			work | werken
+			live | wonen; leven
+			like | leuk vinden
+			eat | eten
+			drink | drinken
+			go | gaan
+			get up | opstaan
+			watch | kijken (naar)
+			play | spelen
+			read | lezen
+			study | studeren
+			every day | elke dag
+			usually | meestal
+			always | altijd
+			never | nooit
+		`,
+			sentences: `
+			I work in an office. | Ik werk op een kantoor.
+			She lives in London. | Zij woont in Londen.
+			He doesn't eat meat. | Hij eet geen vlees.
+			Do you like football? | Hou je van voetbal?
+			My sister studies medicine. | Mijn zus studeert geneeskunde.
+			We usually get up at seven. | We staan meestal om zeven uur op.
+			Does he play the guitar? | Speelt hij gitaar?
+		`,
+			drills: `
+			She ___ in a bank. (work) | works | work; working; is work
+			He ___ TV every evening. (watch) | watches | watchs; watch; watching
+			My brother ___ history. (study) | studies | studys; study; studyes
+			___ you speak English? | Do | Does; Are; Speak
+			She doesn't ___ coffee. (like) | like | likes; liking; to like | Na doesn't geen -s.
+			Werk je hier? | Do you work here? | Work you here?; Are you work here?; Does you work here?
+		`
+		}),
+		lesson({
+			id: 'en-questions',
+			title: 'Who, what, where?',
+			summary: 'Vraagwoorden en vragen stellen',
+			notes: `
+			| | |
+			|---|---|
+			| who | wie |
+			| what | wat |
+			| where | waar |
+			| when | wanneer |
+			| why | waarom |
+			| how | hoe |
+			| which | welke |
+			| whose | van wie |
+			| how much | hoeveel (ontelbaar) |
+			| how many | hoeveel (telbaar) |
+			| how often | hoe vaak |
+
+			Volgorde: **vraagwoord + do/does + onderwerp + werkwoord**: *Where **do** you live?*
+			Met *be* of een hulpwerkwoord (can, will): gewoon omdraaien: *Where **are** you? What **can** I do?*
+
+			Uitzondering: als *who/what* het onderwerp is, geen *do*: ***Who lives** here?* (niet ~~Who does live here?~~).
+		`,
+			words: `
+			who | wie
+			what | wat
+			where | waar
+			when | wanneer
+			why | waarom
+			how | hoe
+			which | welke
+			whose | van wie
+			how much | hoeveel (ontelbaar)
+			how many | hoeveel (telbaar)
+			how often | hoe vaak
+			because | omdat; want
+		`,
+			sentences: `
+			Where do you live? | Waar woon je?
+			What do you do? | Wat doe je (voor werk)?
+			Why are you late? | Waarom ben je te laat?
+			How much is this? | Hoeveel kost dit?
+			How many brothers have you got? | Hoeveel broers heb je?
+			Who lives here? | Wie woont hier?
+			Whose phone is this? | Van wie is deze telefoon?
+			How often do you go to the gym? | Hoe vaak ga je naar de sportschool?
+		`,
+			drills: `
+			___ money do you have? | How much | How many; How often; What many
+			___ people are there? | How many | How much; How often; Who many
+			Waar woon je? | Where do you live? | Where live you?; Where you live?; Where are you live?
+			___ phone is this? – It's Tom's. | Whose | Who's; Who; Which's
+			Wie wil koffie? | Who wants coffee? | Who does want coffee?; Who want coffee?; Whom wants coffee?
+		`
+		}),
+		lesson({
+			id: 'en-time',
+			title: 'What time is it?',
+			summary: 'Dagen, maanden en de klok (pas op met "half")',
+			notes: `
+			In het Engels krijgen dagen en maanden een **hoofdletter**: *Monday, January*.
+
+			### De klok: pas op!
+			| tijd | Engels | niet |
+			|---|---|---|
+			| 2:30 | **half past two** | ~~half three~~ (Brits informeel = 3:30!) |
+			| 2:15 | quarter past two | |
+			| 2:45 | quarter to three | |
+			| 2:20 | twenty past two | |
+			| 2:40 | twenty to three | |
+
+			Het Engelse *half past two* is **half drie**. Je kunt ook gewoon de cijfers zeggen: *two thirty*.
+			**a.m.** = voor 12 uur 's middags, **p.m.** = erna. De 24-uursklok is ongebruikelijk in spreektaal.
+
+			Voorzetsels: **at** + tijd (*at 3 o'clock*), **on** + dag (*on Monday*), **in** + maand/jaar (*in May, in 2026*).
+		`,
+			words: `
+			Monday | maandag
+			Tuesday | dinsdag
+			Wednesday | woensdag
+			Thursday | donderdag
+			Friday | vrijdag
+			Saturday | zaterdag
+			Sunday | zondag
+			weekend | weekend
+			month | maand
+			year | jaar
+			hour | uur
+			minute | minuut
+			half past | half (+ volgend uur in het Nederlands)
+			quarter | kwartier
+			o'clock | uur (hele uren)
+			today | vandaag
+			tomorrow | morgen
+			yesterday | gisteren
+		`,
+			sentences: `
+			What time is it? | Hoe laat is het?
+			It's half past seven. | Het is half acht.
+			The film starts at nine o'clock. | De film begint om negen uur.
+			I work from Monday to Friday. | Ik werk van maandag tot en met vrijdag.
+			My birthday is in June. | Mijn verjaardag is in juni.
+			See you on Saturday! | Tot zaterdag!
+			It's quarter to four. | Het is kwart voor vier.
+		`,
+			drills: `
+			Half drie (2:30): | half past two | half three; half past three; half to three | Engels telt vanaf het vorige uur.
+			Kwart over negen: | quarter past nine | quarter to nine; quarter over nine; quarter past ten
+			___ Monday | on | in; at; by
+			___ 6 o'clock | at | on; in; by
+			___ July | in | on; at; by
+		`
+		}),
+		lesson({
+			id: 'en-food',
+			title: 'Food and drink',
+			summary: 'Eten, drinken, a/an/some/any',
+			notes: `
+			### a / an
+			**a** voor een medeklinker-**klank**, **an** voor een klinker-**klank**: *a banana, **an** apple, **an** hour* (h stil), *a university* ("joe").
+
+			### some / any
+			- **some** in bevestigende zinnen: *I'd like **some** water.*
+			- **any** in vragen en ontkenningen: *Have you got **any** milk? There isn't **any** bread.*
+			- **some** in aanbiedingen en verzoeken: *Would you like **some** tea?*
+
+			### Ontelbaar
+			Sommige woorden zijn in het Engels ontelbaar (geen *a*, geen meervoud): *water, bread, rice, milk, advice, information, furniture, news*.
+			Dus: ~~an advice~~ → *some advice / a piece of advice*.
+
+			**I'd like** (= I would like) is de beleefde manier om iets te bestellen.
+		`,
+			words: `
+			bread | brood
+			cheese | kaas
+			butter | boter
+			egg | ei
+			apple | appel
+			banana | banaan
+			water | water
+			coffee | koffie
+			tea | thee
+			milk | melk
+			beer | bier
+			breakfast | ontbijt
+			lunch | lunch
+			dinner | avondeten
+			hungry | hongerig
+			thirsty | dorstig
+			delicious | heerlijk; lekker
+		`,
+			sentences: `
+			I'm hungry. | Ik heb honger.
+			Are you thirsty? | Heb je dorst?
+			I'd like a cheese sandwich, please. | Ik wil graag een broodje kaas.
+			Would you like some tea? | Wil je wat thee?
+			We haven't got any milk. | We hebben geen melk.
+			This soup is delicious! | Deze soep is heerlijk!
+			Can I have the bill, please? | Mag ik de rekening, alstublieft?
+		`,
+			drills: `
+			___ apple | an | a; the an; some
+			___ hour | an | a; one; some | De h is stil.
+			___ university | a | an; one; the an | "University" begint met een j-klank.
+			Is there ___ sugar? | any | some; a; many
+			Ik heb honger: | I'm hungry. | I have hunger.; I am hunger.; I have hungry.
+			I need some ___. (advies) | advice | advices; an advice; advise
+		`
+		}),
+		lesson({
+			id: 'en-town',
+			title: 'In town',
+			summary: 'There is / there are, plekken en de weg vragen',
+			notes: `
+			### There is / there are
+			- **There's** a bakery on the corner. (enkelvoud)
+			- **There are** two supermarkets. (meervoud)
+			- **Is there** a bank near here? **Are there** any shops?
+
+			Nederlanders zeggen vaak ~~It has a nice park~~ voor "Er is een mooi park" — dat is fout. Gebruik ***There's** a nice park*.
+
+			### De weg wijzen
+			| | |
+			|---|---|
+			| go straight on | ga rechtdoor |
+			| turn left / right | sla linksaf / rechtsaf |
+			| take the first left | neem de eerste links |
+			| on the corner | op de hoek |
+			| opposite | tegenover |
+			| next to | naast |
+			| between | tussen |
+		`,
+			words: `
+			street | straat
+			station | station
+			shop | winkel
+			supermarket | supermarkt
+			bank | bank (geld)
+			bakery | bakkerij
+			square | plein
+			bridge | brug
+			park | park
+			hospital | ziekenhuis
+			left | links
+			right | rechts
+			straight on | rechtdoor
+			corner | hoek
+			opposite | tegenover
+			near | dichtbij
+			far | ver
+		`,
+			sentences: `
+			Is there a bank near here? | Is er een bank hier in de buurt?
+			There's a café opposite the station. | Er is een café tegenover het station.
+			There are a lot of bikes in Amsterdam. | Er zijn veel fietsen in Amsterdam.
+			Go straight on and turn left. | Ga rechtdoor en sla linksaf.
+			The hospital is next to the park. | Het ziekenhuis is naast het park.
+			Is it far from here? | Is het ver hiervandaan?
+			Excuse me, how do I get to the museum? | Pardon, hoe kom ik bij het museum?
+		`,
+			drills: `
+			___ a nice park in my town. | There's | It has; There are; It's
+			___ three bedrooms in the house. | There are | There's; It has; They are
+			Sla rechtsaf: | turn right | go right off; turn rightoff; take right
+			The bank is ___ the post office. (naast) | next to | beside of; near of; next
+		`
+		}),
+		lesson({
+			id: 'en-adjectives',
+			title: 'Big, red, beautiful',
+			summary: 'Kleuren en bijvoeglijke naamwoorden',
+			notes: `
+			Engelse bijvoeglijke naamwoorden veranderen **nooit**: geen -e, geen meervoud.
+			*a **big** house, the **big** houses, a **red** car* (niet ~~a rede car~~ of ~~bigs houses~~).
+
+			Ze staan **voor** het zelfstandig naamwoord: *a **new** phone* — of na *be*: *My phone is **new**.*
+
+			Versterken: **very** (erg), **really** (echt), **quite** (behoorlijk), **too** (te): *It's **too** expensive.*
+
+			Volgorde bij meerdere: mening – grootte – leeftijd – kleur: *a **beautiful big old red** car*.
+		`,
+			words: `
+			red | rood
+			blue | blauw
+			yellow | geel
+			green | groen
+			black | zwart
+			white | wit
+			orange | oranje
+			grey | grijs
+			brown | bruin
+			pink | roze
+			big | groot
+			small | klein
+			beautiful | mooi
+			ugly | lelijk
+			new | nieuw
+			old | oud
+			expensive | duur
+			cheap | goedkoop
+		`,
+			sentences: `
+			I've got a red bike. | Ik heb een rode fiets.
+			The house is very big. | Het huis is erg groot.
+			These shoes are too expensive. | Deze schoenen zijn te duur.
+			She has beautiful eyes. | Ze heeft prachtige ogen.
+			It's a small old car. | Het is een kleine oude auto.
+			My new phone is black. | Mijn nieuwe telefoon is zwart.
+		`,
+			drills: `
+			de grote huizen: | the big houses | the bigs houses; the bige houses; the houses big
+			een nieuwe auto: | a new car | a newe car; a car new; an new car
+			Het is te duur: | It's too expensive. | It's to expensive.; It's two expensive.; It's also expensive.
+			a ___ car (mooi, oud) | beautiful old | old beautiful; beautifully old; beautifuls old
+		`
+		})
+	]
+);

src/lib/language-learner/courses/en/a2.ts

@@ -0,0 +1,419 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a2',
+	'A2',
+	'Elementary',
+	'Present continuous, de verleden tijd, toekomst, vergelijken en modale werkwoorden.',
+	[
+		lesson({
+			id: 'en-continuous',
+			title: 'I am working',
+			summary: 'Present continuous versus present simple',
+			notes: `
+			**Present continuous** = *am/is/are + werkwoord-ing*: iets wat **nu** of **tijdelijk** gebeurt.
+			*I'**m working** right now. She'**s living** with her parents this year.*
+
+			**Present simple** = gewoontes en feiten: *I **work** in Utrecht. She **lives** in Leeds.*
+
+			| nu / tijdelijk | gewoonte / altijd |
+			|---|---|
+			| now, right now, at the moment, today, this week | always, usually, every day, often, never |
+
+			Nederlands heeft hier vaak geen verschil: "ik werk" kan beide zijn. Denk aan "ik **ben aan het** werken" → continuous.
+
+			Sommige werkwoorden (toestanden) krijgen bijna nooit -ing: *know, like, want, need, understand, believe, own*.
+			~~I'm knowing~~ → *I **know***.
+
+			Spelling: *make → making, swim → swimming, lie → lying*.
+		`,
+			words: `
+			right now | nu; op dit moment
+			at the moment | op het moment
+			this week | deze week
+			wait | wachten
+			rain | regenen
+			cook | koken
+			listen | luisteren
+			look for | zoeken naar
+			wear | dragen (kleding)
+			understand | begrijpen
+			know | weten; kennen
+			want | willen
+			need | nodig hebben
+		`,
+			sentences: `
+			What are you doing? | Wat ben je aan het doen?
+			I'm cooking dinner. | Ik ben het avondeten aan het koken.
+			It's raining again. | Het regent weer.
+			She's wearing a blue dress today. | Ze draagt vandaag een blauwe jurk.
+			I usually walk to work, but today I'm taking the bus. | Meestal loop ik naar mijn werk, maar vandaag neem ik de bus.
+			I don't understand the question. | Ik begrijp de vraag niet.
+			We're looking for the station. | We zoeken het station.
+		`,
+			drills: `
+			Look! It ___. | is snowing | snows; snowing; is snow
+			I ___ to work every day. | cycle | am cycling; cycling; cycles
+			She ___ the answer. (weten) | knows | is knowing; know; knowing | Know krijgt geen -ing.
+			Wat ben je aan het doen? | What are you doing? | What do you doing?; What are you do?; What you are doing?
+			make + ing | making | makeing; makking; maken
+			swim + ing | swimming | swiming; swimmming; swimeing
+		`
+		}),
+		lesson({
+			id: 'en-past-simple',
+			title: 'Yesterday I went',
+			summary: 'Past simple: regelmatig, onregelmatig en did',
+			notes: `
+			De **past simple** gebruik je voor iets dat **afgelopen** is, op een bepaald moment in het verleden: *yesterday, last week, in 2019, two days ago*.
+
+			### Regelmatig: -ed
+			*work → work**ed**, live → live**d**, stop → stop**ped**, study → stud**ied***.
+
+			### Onregelmatig
+			Veel gebruikte werkwoorden zijn onregelmatig: *go → **went**, have → **had**, see → **saw**, buy → **bought***. Oefen ze met de drill **Irregular verbs**.
+
+			### Vragen en ontkenning met did
+			- *I **didn't** go.* (niet ~~didn't went~~)
+			- ***Did** you **see** it?* (niet ~~Did you saw~~)
+
+			**Ago** = geleden, en komt **na** de tijd: *three years **ago***.
+			*Be* is was/were: *I **was** tired. They **were** late.*
+		`,
+			words: `
+			yesterday | gisteren
+			last week | vorige week
+			last year | vorig jaar
+			ago | geleden
+			went | ging
+			had | had
+			saw | zag
+			bought | kocht
+			ate | at
+			came | kwam
+			was | was
+			were | waren
+			did | deed
+			visit | bezoeken
+			stay | blijven; logeren
+		`,
+			sentences: `
+			I went to London last year. | Ik ging vorig jaar naar Londen.
+			We stayed in a small hotel. | We verbleven in een klein hotel.
+			She bought a new laptop yesterday. | Ze kocht gisteren een nieuwe laptop.
+			Did you see the match? | Heb je de wedstrijd gezien?
+			I didn't have time. | Ik had geen tijd.
+			They were very tired. | Ze waren heel moe.
+			I met him three years ago. | Ik heb hem drie jaar geleden ontmoet.
+		`,
+			drills: `
+			I ___ to Paris last summer. (go) | went | goed; gone; go
+			She ___ a cake yesterday. (make) | made | maked; make; maden
+			I didn't ___ him. (see) | see | saw; seen; seeing | Na didn't: het hele werkwoord.
+			___ you enjoy the film? | Did | Do; Were; Have
+			drie jaar geleden: | three years ago | ago three years; before three years; three years before
+			stop → past | stopped | stoped; stopt; stopd
+		`
+		}),
+		lesson({
+			id: 'en-future',
+			title: 'Going to and will',
+			summary: 'De toekomst: going to, will en de present continuous',
+			notes: `
+			| vorm | gebruik | voorbeeld |
+			|---|---|---|
+			| **going to** | plannen, iets wat je al besloten hebt | *I'm going to buy a car.* |
+			| **will** | een besluit op dit moment, beloftes, voorspellingen | *I'll help you! It will rain.* |
+			| **present continuous** | afspraken met tijd en plaats | *I'm meeting Sam at 8.* |
+
+			Spontaan besluit: telefoon gaat → *I'**ll** get it!* (niet ~~I'm going to get it~~).
+			Voorspelling met bewijs: *Look at those clouds! It's **going to** rain.*
+
+			**Shall I/we …?** voor voorstellen: ***Shall** we go?* — Zullen we gaan?
+			Let op: Nederlands "ik wil" is **I want**, niet *I will*!
+		`,
+			words: `
+			tomorrow | morgen
+			next week | volgende week
+			next year | volgend jaar
+			soon | binnenkort
+			later | later
+			plan | plan; plannen
+			going to | gaan (toekomst)
+			will | zullen
+			shall | zullen (voorstel)
+			probably | waarschijnlijk
+			maybe | misschien
+			promise | beloven
+		`,
+			sentences: `
+			I'm going to learn Korean next year. | Ik ga volgend jaar Koreaans leren.
+			I'll call you tomorrow. | Ik bel je morgen.
+			It's going to rain. | Het gaat regenen.
+			Shall we get something to eat? | Zullen we iets gaan eten?
+			I'm meeting my sister at six. | Ik zie mijn zus om zes uur.
+			I think she'll love it. | Ik denk dat ze het geweldig zal vinden.
+			I promise I won't be late. | Ik beloof dat ik niet te laat kom.
+		`,
+			drills: `
+			The phone is ringing. – I ___ it! | 'll get | 'm going to get; get; 'm getting
+			We've booked the tickets. We ___ to Spain. | 're going to go | 'll go; go; shall go
+			___ we dance? (Zullen we) | Shall | Will; Want; Going
+			Ik wil een koffie: | I want a coffee. | I will a coffee.; I will have want a coffee.; I wish a coffee.
+			will not → | won't | willn't; wont; will'nt
+		`
+		}),
+		lesson({
+			id: 'en-comparing',
+			title: 'Bigger and the biggest',
+			summary: 'Trappen van vergelijking',
+			notes: `
+			| | vergrotende trap | overtreffende trap |
+			|---|---|---|
+			| kort (1 lettergreep) | + **-er**: tall**er** | **the** + **-est**: the tall**est** |
+			| op -y | **-ier**: happ**ier** | the happ**iest** |
+			| lang (2+ lettergrepen) | **more** beautiful | **the most** beautiful |
+			| onregelmatig | good → **better**, bad → **worse**, far → **further** | **the best**, **the worst**, **the furthest** |
+
+			Spelling: *big → bi**gg**er, hot → ho**tt**er*.
+
+			**than** = dan: *She's older **than** me.* (niet ~~then~~!)
+			**as … as** = net zo … als: *He's **as** tall **as** his dad.*
+		`,
+			words: `
+			bigger | groter
+			smaller | kleiner
+			better | beter
+			best | best
+			worse | slechter
+			worst | slechtst
+			more | meer
+			most | meest
+			than | dan
+			as … as | net zo … als
+			tall | lang (persoon)
+			fast | snel
+			easy | makkelijk
+			difficult | moeilijk
+		`,
+			sentences: `
+			My brother is taller than me. | Mijn broer is langer dan ik.
+			This is the best pizza in town. | Dit is de beste pizza van de stad.
+			English is easier than Dutch. | Engels is makkelijker dan Nederlands.
+			It's the most beautiful city in the world. | Het is de mooiste stad ter wereld.
+			Today is worse than yesterday. | Vandaag is erger dan gisteren.
+			She's as clever as her sister. | Ze is net zo slim als haar zus.
+		`,
+			drills: `
+			He is ___ than me. (old) | older | more old; oldest; elder then
+			This is ___ restaurant in town. (good) | the best | the better; the goodest; the most good
+			The test was ___ than I thought. (difficult) | more difficult | difficulter; most difficult; more difficulter
+			groter dan: | bigger than | biger than; bigger then; more big than
+			She's ___ than her sister. (happy) | happier | happyer; more happy; happiest
+		`
+		}),
+		lesson({
+			id: 'en-modals',
+			title: 'Can, must, should',
+			summary: 'Modale werkwoorden',
+			notes: `
+			| | betekenis |
+			|---|---|
+			| can / can't | kunnen, mogen (informeel) |
+			| could | kon, zou kunnen (beleefd) |
+			| must / mustn't | moeten (eigen gevoel) / **niet mogen** |
+			| have to / don't have to | moeten (regel van buitenaf) / **niet hoeven** |
+			| should / shouldn't | zouden moeten (advies) |
+			| may | mogen (formeel), misschien |
+
+			Na een modaal werkwoord: **geen to en geen -s**: *She **can swim**.* (niet ~~cans~~, niet ~~can to swim~~).
+
+			**Grote valkuil**: *mustn't* = niet mogen, *don't have to* = niet hoeven.
+			- *You **mustn't** smoke here.* — Je mag hier niet roken.
+			- *You **don't have to** come.* — Je hoeft niet te komen.
+		`,
+			words: `
+			can | kunnen
+			could | kon; zou kunnen
+			must | moeten
+			mustn't | niet mogen
+			have to | moeten
+			don't have to | niet hoeven
+			should | zou moeten
+			may | mogen; misschien
+			allowed | toegestaan
+			rule | regel
+			advice | advies
+		`,
+			sentences: `
+			Can you swim? | Kun je zwemmen?
+			Could you help me, please? | Zou je me kunnen helpen?
+			You mustn't park here. | Je mag hier niet parkeren.
+			I have to work on Saturday. | Ik moet zaterdag werken.
+			You don't have to pay. | Je hoeft niet te betalen.
+			You should see a doctor. | Je zou naar een dokter moeten gaan.
+			May I come in? | Mag ik binnenkomen?
+		`,
+			drills: `
+			Je hoeft niet te komen: | You don't have to come. | You mustn't come.; You haven't to come.; You don't must come.
+			Je mag hier niet roken: | You mustn't smoke here. | You don't have to smoke here.; You mustn't to smoke here.; You not must smoke here.
+			She ___ speak three languages. | can | cans; can to; is can
+			You look ill. You ___ go home. (advies) | should | must to; would; shall
+			___ you open the window, please? (beleefd) | Could | Must; Should; Shall
+		`
+		}),
+		lesson({
+			id: 'en-prepositions',
+			title: 'In, on, at',
+			summary: 'Voorzetsels van tijd en plaats',
+			notes: `
+			### Tijd
+			| at | on | in |
+			|---|---|---|
+			| kloktijd: at 5 o'clock | dagen: on Monday | maanden: in May |
+			| at night, at the weekend (BrE) | datums: on 3 March | jaren: in 2026 |
+			| at Christmas | on my birthday | seizoenen: in (the) summer |
+			| | | dagdelen: in the morning |
+
+			### Plaats
+			- **at** een punt/adres: *at home, at work, at school, at the station, at 10 Baker Street*
+			- **in** een ruimte/stad/land: *in the kitchen, in London, in the car*
+			- **on** een oppervlak/straat/vervoer: *on the table, on the wall, on the bus, on Oxford Street*
+
+			Let op: *in the car* maar *on the bus/train/plane*.
+		`,
+			words: `
+			at | om; bij; op
+			on | op
+			in | in
+			at home | thuis
+			at work | op het werk
+			at night | 's nachts
+			in the morning | 's ochtends
+			on the bus | in de bus
+			on the wall | aan de muur
+			during | tijdens
+			until | tot
+			for | voor; gedurende
+		`,
+			sentences: `
+			I'm at home. | Ik ben thuis.
+			She lives in Rotterdam. | Ze woont in Rotterdam.
+			The meeting is on Tuesday at ten. | De vergadering is dinsdag om tien uur.
+			I was born in 1998. | Ik ben in 1998 geboren.
+			There's a picture on the wall. | Er hangt een schilderij aan de muur.
+			I read on the train. | Ik lees in de trein.
+			We go skiing in winter. | We gaan in de winter skiën.
+		`,
+			drills: `
+			___ Friday | on | in; at; by
+			___ 2020 | in | on; at; by
+			___ 7 p.m. | at | on; in; by
+			___ the morning | in | on; at; by
+			I'm ___ work. | at | on; in; by
+			I left my bag ___ the bus. | on | in; at; by
+			There's a clock ___ the wall. | on | at; in; by
+		`
+		}),
+		lesson({
+			id: 'en-quantity',
+			title: 'Much, many, a lot of',
+			summary: 'Telbaar en ontelbaar',
+			notes: `
+			| | telbaar (books, people) | ontelbaar (water, money, time) |
+			|---|---|---|
+			| veel (vraag/ontkenning) | **many** | **much** |
+			| veel (bevestigend) | a lot of / lots of | a lot of / lots of |
+			| een paar / een beetje | **a few** | **a little** |
+			| weinig | few | little |
+			| minder | **fewer** | **less** |
+			| hoeveel | how **many** | how **much** |
+
+			*There aren't **many** people. I don't have **much** time. I've got **a lot of** friends.*
+
+			**Money, time, information, advice, furniture, luggage, news, homework** zijn ontelbaar in het Engels.
+		`,
+			words: `
+			much | veel (ontelbaar)
+			many | veel (telbaar)
+			a lot of | veel
+			a few | een paar
+			a little | een beetje
+			few | weinig (telbaar)
+			little | weinig (ontelbaar)
+			money | geld
+			time | tijd
+			information | informatie
+			luggage | bagage
+			furniture | meubels
+			homework | huiswerk
+		`,
+			sentences: `
+			I don't have much time. | Ik heb niet veel tijd.
+			How many people are coming? | Hoeveel mensen komen er?
+			How much luggage do you have? | Hoeveel bagage heb je?
+			There are a few problems. | Er zijn een paar problemen.
+			Can I have a little milk? | Mag ik een beetje melk?
+			She's got a lot of friends. | Ze heeft veel vrienden.
+			We need more information. | We hebben meer informatie nodig.
+		`,
+			drills: `
+			How ___ money do you need? | much | many; lot; few
+			How ___ brothers do you have? | many | much; lot; little
+			I have ___ questions. (een paar) | a few | a little; few of; a bit
+			We've got ___ time left. (een beetje) | a little | a few; few; many
+			There were ___ people than last year. | fewer | less; few; lesser
+			Ik heb veel huiswerk: | I have a lot of homework. | I have many homeworks.; I have much homeworks.; I have a lot homeworks.
+		`
+		}),
+		lesson({
+			id: 'en-travel',
+			title: 'Travelling',
+			summary: 'Reizen, vervoer en het vliegveld',
+			notes: `
+			Handige werkwoorden:
+			- **catch / take** a train — de trein nemen; **miss** — missen
+			- **get on / get off** — instappen / uitstappen (bus, trein, vliegtuig); **get in / get out of** — (auto, taxi)
+			- **check in** — inchecken; **board** — aan boord gaan
+			- **book** — boeken, reserveren
+
+			**Travel** is een werkwoord of ontelbaar; een reis is **a trip** (kort) of **a journey** (de tocht zelf).
+			~~a travel~~ → *a trip*.
+		`,
+			words: `
+			trip | reis; uitstapje
+			journey | reis; tocht
+			ticket | kaartje
+			return ticket | retourtje
+			single ticket | enkeltje
+			platform | perron
+			delay | vertraging
+			luggage | bagage
+			suitcase | koffer
+			passport | paspoort
+			airport | vliegveld
+			flight | vlucht
+			get on | instappen
+			get off | uitstappen
+			miss | missen
+			book | boeken
+			abroad | in het buitenland
+		`,
+			sentences: `
+			A return ticket to Brighton, please. | Een retourtje Brighton, alstublieft.
+			Which platform does the train leave from? | Van welk perron vertrekt de trein?
+			The flight is delayed by two hours. | De vlucht heeft twee uur vertraging.
+			We missed the last bus. | We hebben de laatste bus gemist.
+			Get off at the next stop. | Stap uit bij de volgende halte.
+			How was your trip? | Hoe was je reis?
+			We're going abroad this summer. | We gaan deze zomer naar het buitenland.
+		`,
+			drills: `
+			Hoe was je reis? | How was your trip? | How was your travel?; How was your journey travel?; How was you trip?
+			___ the bus at the station. (uitstappen) | Get off | Get out; Go off; Step off of
+			I ___ the train! (missed) | missed | lost; mist; failed
+			Een enkeltje: | a single ticket | a one ticket; an alone ticket; a single travel
+		`
+		})
+	]
+);

src/lib/language-learner/courses/en/b1.ts

@@ -0,0 +1,401 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b1',
+	'B1',
+	'Intermediate',
+	'Present perfect, phrasal verbs, conditionals, passief en indirecte rede.',
+	[
+		lesson({
+			id: 'en-present-perfect',
+			title: 'I have seen it',
+			summary: 'Present perfect versus past simple (dé Nederlandse valkuil)',
+			notes: `
+			Nederlands zegt "ik **heb** hem gisteren **gezien**", maar het Engels gebruikt dan de **past simple**: *I **saw** him yesterday*.
+
+			| present perfect (have + voltooid deelwoord) | past simple |
+			|---|---|
+			| **geen** afgelopen tijdstip | **wel** een afgelopen tijdstip |
+			| ervaring: *I've been to Japan.* | *I went to Japan **in 2019**.* |
+			| resultaat nu: *I've lost my keys.* | *I lost my keys **yesterday**.* |
+			| tot nu toe: *I've lived here **for** ten years.* | *I lived there **for** ten years* (woon er niet meer) |
+			| ever, never, already, yet, just, so far | yesterday, ago, last …, in 2019, when … |
+
+			### for / since
+			*I've lived here **for** five years* (duur) / ***since** 2021* (beginpunt).
+			Nederlands "ik woon hier **al vijf jaar**" is dus ***I've lived / I've been living** here for five years* — niet ~~I live here since five years~~!
+		`,
+			words: `
+			ever | ooit
+			never | nooit
+			already | al
+			yet | al (vraag); nog (niet)
+			just | net; zojuist
+			so far | tot nu toe
+			for | (al) … lang
+			since | sinds
+			been | geweest
+			seen | gezien
+			done | gedaan
+			lost | verloren
+			finished | af; klaar
+		`,
+			sentences: `
+			Have you ever been to Canada? | Ben je ooit in Canada geweest?
+			I've never eaten sushi. | Ik heb nog nooit sushi gegeten.
+			I saw him yesterday. | Ik heb hem gisteren gezien.
+			She's just left. | Ze is net weggegaan.
+			Have you finished yet? | Ben je al klaar?
+			I've lived here for ten years. | Ik woon hier al tien jaar.
+			We've known each other since 2015. | We kennen elkaar sinds 2015.
+			I've lost my phone. | Ik ben mijn telefoon kwijt.
+		`,
+			drills: `
+			Ik heb hem gisteren gezien: | I saw him yesterday. | I have seen him yesterday.; I've saw him yesterday.; I have see him yesterday. | Een afgelopen tijdstip → past simple.
+			Ik woon hier al drie jaar: | I've lived here for three years. | I live here since three years.; I live here for three years.; I've lived here since three years.
+			I've worked here ___ 2020. | since | for; from; ago
+			I've worked here ___ six months. | for | since; from; ago
+			___ you ever ___ to Italy? | Have … been | Did … go; Have … go; Were … been
+			She hasn't called ___. | yet | already; still; ever
+		`
+		}),
+		lesson({
+			id: 'en-phrasal-1',
+			title: 'Get up, give up',
+			summary: 'Veelgebruikte phrasal verbs',
+			notes: `
+			Een **phrasal verb** is werkwoord + partikel met een nieuwe betekenis. Net als Nederlandse scheidbare werkwoorden (opgeven, uitzoeken)!
+
+			| phrasal verb | betekenis |
+			|---|---|
+			| get up | opstaan |
+			| give up | opgeven |
+			| look for | zoeken naar |
+			| look after | zorgen voor |
+			| find out | ontdekken, uitzoeken |
+			| turn on / off | aanzetten / uitzetten |
+			| put on / take off | aantrekken / uittrekken |
+			| pick up | oppakken, ophalen |
+			| call back | terugbellen |
+			| run out of | door … heen raken |
+			| come back | terugkomen |
+			| go out | uitgaan |
+
+			Met een voornaamwoord staat dat **tussen** werkwoord en partikel: *Turn **it** off* (niet ~~Turn off it~~).
+		`,
+			words: `
+			get up | opstaan
+			give up | opgeven
+			look for | zoeken naar
+			look after | zorgen voor
+			find out | ontdekken; uitzoeken
+			turn on | aanzetten
+			turn off | uitzetten
+			put on | aantrekken
+			take off | uittrekken; opstijgen
+			pick up | oppakken; ophalen
+			call back | terugbellen
+			run out of | door … heen raken
+			go out | uitgaan
+			come back | terugkomen
+		`,
+			sentences: `
+			I get up at seven every day. | Ik sta elke dag om zeven uur op.
+			Don't give up! | Geef niet op!
+			Can you look after my cat? | Kun jij voor mijn kat zorgen?
+			Please turn off your phone. | Zet alsjeblieft je telefoon uit.
+			Put your coat on, it's cold. | Trek je jas aan, het is koud.
+			I'll pick you up at eight. | Ik haal je om acht uur op.
+			We've run out of milk. | De melk is op.
+			I'll call you back later. | Ik bel je later terug.
+		`,
+			drills: `
+			Zet de tv uit: | Turn the TV off. | Turn off it.; Turn out the TV.; Make the TV off.
+			Zet hem uit: | Turn it off. | Turn off it.; Turn it out.; Off turn it.
+			Ik haal je op: | I'll pick you up. | I'll pick up you.; I'll get you up.; I'll take you up.
+			I'm looking ___ my keys. (zoeken) | for | after; out; up
+			She looks ___ her little brother. (zorgen voor) | after | for; at; out
+			We ran ___ of petrol. | out | off; over; away
+		`
+		}),
+		lesson({
+			id: 'en-conditionals',
+			title: 'If it rains…',
+			summary: 'First en second conditional',
+			notes: `
+			### First conditional — echt mogelijk
+			**If + present simple, will + werkwoord**
+			*If it **rains**, I**'ll stay** home.* (niet ~~If it will rain~~!)
+
+			### Second conditional — onwaarschijnlijk of denkbeeldig
+			**If + past simple, would + werkwoord**
+			*If I **had** more money, I**'d travel** the world.*
+			*If I **were** you, I**'d** say sorry.* (bij *I/he/she* mag *were*, en in "if I were you" is het de norm)
+
+			Ook **unless** (tenzij) = if … not: *I won't go **unless** you come.*
+			**When** voor iets dat zeker gebeurt: ***When** I get home, I'll call you.*
+		`,
+			words: `
+			if | als; indien
+			unless | tenzij
+			would | zou
+			when | wanneer; als
+			as soon as | zodra
+			in case | voor het geval dat
+			rich | rijk
+			lottery | loterij
+			win | winnen
+			miss | missen
+		`,
+			sentences: `
+			If it rains, we'll stay inside. | Als het regent, blijven we binnen.
+			If I had more time, I'd learn to play the piano. | Als ik meer tijd had, zou ik piano leren spelen.
+			If I were you, I'd take the job. | Als ik jou was, zou ik de baan aannemen.
+			What would you do if you won the lottery? | Wat zou je doen als je de loterij won?
+			I'll call you when I arrive. | Ik bel je als ik aankom.
+			You'll miss the train unless you hurry. | Je mist de trein, tenzij je opschiet.
+			Take an umbrella in case it rains. | Neem een paraplu mee voor het geval het regent.
+		`,
+			drills: `
+			If it ___ sunny tomorrow, we'll go to the beach. | is | will be; would be; was | Na if geen will.
+			If I ___ rich, I would buy a boat. | were | am; will be; would be
+			If I had time, I ___ help you. | would | will; did; had
+			Als ik jou was…: | If I were you… | If I would be you…; If I am you…; When I were you…
+			I won't come ___ you invite me. (tenzij) | unless | if; except; when
+		`
+		}),
+		lesson({
+			id: 'en-passive',
+			title: 'It was built in 1900',
+			summary: 'De lijdende vorm',
+			notes: `
+			**Passive** = vorm van **be** + **voltooid deelwoord**. Het Engels gebruikt altijd *be* (Nederlands: *worden* én *zijn*).
+
+			| tijd | voorbeeld |
+			|---|---|
+			| present simple | English **is spoken** here. |
+			| present continuous | The road **is being repaired**. |
+			| past simple | The house **was built** in 1900. |
+			| present perfect | My bike **has been stolen**. |
+			| will | It **will be finished** tomorrow. |
+			| modaal | It **can be done**. |
+
+			De uitvoerder krijgt **by**: *Hamlet was written **by** Shakespeare.*
+
+			Nederlanders zeggen vaak ~~I am born in 1995~~; het is ***I was born** in 1995*.
+		`,
+			words: `
+			built | gebouwd
+			written | geschreven
+			made | gemaakt
+			stolen | gestolen
+			sold | verkocht
+			spoken | gesproken
+			invented | uitgevonden
+			born | geboren
+			by | door
+			repair | repareren
+			deliver | bezorgen
+		`,
+			sentences: `
+			English is spoken all over the world. | Engels wordt over de hele wereld gesproken.
+			This bridge was built in 1890. | Deze brug is in 1890 gebouwd.
+			My bike has been stolen. | Mijn fiets is gestolen.
+			The package will be delivered tomorrow. | Het pakket wordt morgen bezorgd.
+			I was born in Rotterdam. | Ik ben in Rotterdam geboren.
+			The telephone was invented by Bell. | De telefoon is uitgevonden door Bell.
+			The road is being repaired. | De weg wordt gerepareerd.
+		`,
+			drills: `
+			Ik ben in 1999 geboren: | I was born in 1999. | I am born in 1999.; I have been born in 1999.; I was borned in 1999.
+			The book ___ by Orwell. | was written | is writing; was wrote; has written
+			Mijn telefoon is gestolen: | My phone has been stolen. | My phone is stolen from me.; My phone has stolen.; My phone was being steal.
+			The room ___ every day. (cleaned) | is cleaned | cleans; is cleaning; is clean
+			It will ___ tomorrow. | be finished | finished; being finished; been finished
+		`
+		}),
+		lesson({
+			id: 'en-relative',
+			title: 'Who, which, that',
+			summary: 'Betrekkelijke bijzinnen',
+			notes: `
+			| | gebruik |
+			|---|---|
+			| **who** | mensen: *the man **who** lives next door* |
+			| **which** | dingen, dieren: *the book **which** I bought* |
+			| **that** | mensen én dingen (alleen in bepalende bijzinnen) |
+			| **whose** | van wie / waarvan: *the girl **whose** dad is a pilot* |
+			| **where** | waar: *the town **where** I grew up* |
+
+			Als het betrekkelijk voornaamwoord het **lijdend voorwerp** is, mag je het weglaten: *the book (that) I bought*.
+
+			Met komma's (extra informatie, niet-bepalend) **nooit** *that*: *My brother, **who** lives in Spain, is a chef.*
+		`,
+			words: `
+			who | die (mensen)
+			which | die; dat (dingen)
+			that | die; dat
+			whose | wiens; van wie
+			where | waar
+			neighbour | buurman; buurvrouw
+			grow up | opgroeien
+			recommend | aanraden
+		`,
+			sentences: `
+			The woman who lives next door is a doctor. | De vrouw die hiernaast woont, is arts.
+			This is the book that I told you about. | Dit is het boek waarover ik je vertelde.
+			That's the restaurant where we met. | Dat is het restaurant waar we elkaar ontmoetten.
+			I have a friend whose mother is Korean. | Ik heb een vriend wiens moeder Koreaans is.
+			The film we watched was boring. | De film die we keken was saai.
+			My sister, who lives in Berlin, is visiting us. | Mijn zus, die in Berlijn woont, komt bij ons op bezoek.
+		`,
+			drills: `
+			the man ___ helped me | who | which; whose; where
+			the car ___ I bought | which | who; whose; where
+			the town ___ I was born | where | which; who; that where
+			a girl ___ father is famous | whose | who's; who; which
+			My mum, ___ is 60, loves hiking. | who | that; which; whose | Met komma's geen that.
+		`
+		}),
+		lesson({
+			id: 'en-used-to',
+			title: 'I used to…',
+			summary: 'Used to, be used to en get used to',
+			notes: `
+			Drie vormen die op elkaar lijken:
+
+			| | betekenis | voorbeeld |
+			|---|---|---|
+			| **used to** + werkwoord | vroeger (nu niet meer) | *I **used to smoke**.* — Ik rookte vroeger. |
+			| **be used to** + -ing / zelfst. nw. | gewend zijn aan | *I'**m used to getting** up early.* |
+			| **get used to** + -ing / zelfst. nw. | wennen aan | *You'll **get used to** the weather.* |
+
+			Vraag en ontkenning van *used to*: *Did you **use to** …? I **didn't use to** …* (zonder d).
+		`,
+			words: `
+			used to | vroeger (deed ik)
+			be used to | gewend zijn aan
+			get used to | wennen aan
+			anymore | niet meer
+			childhood | jeugd
+			habit | gewoonte
+			smoke | roken
+			early | vroeg
+			noise | lawaai
+		`,
+			sentences: `
+			I used to live in Amsterdam. | Ik woonde vroeger in Amsterdam.
+			She didn't use to like coffee. | Vroeger hield ze niet van koffie.
+			I'm used to working late. | Ik ben gewend om laat te werken.
+			You'll get used to the noise. | Je went wel aan het lawaai.
+			Did you use to play football? | Speelde jij vroeger voetbal?
+			I don't smoke anymore. | Ik rook niet meer.
+		`,
+			drills: `
+			Ik speelde vroeger piano: | I used to play the piano. | I use to play the piano.; I was used to play the piano.; I used to playing the piano.
+			Ik ben gewend aan vroeg opstaan: | I'm used to getting up early. | I used to get up early.; I'm used to get up early.; I'm use to getting up early.
+			Did you ___ live here? | use to | used to; using to; used
+			It takes time to get used to ___ on the left. | driving | drive; drove; driven
+		`
+		}),
+		lesson({
+			id: 'en-gerund',
+			title: 'I enjoy swimming',
+			summary: 'Gerund (-ing) of infinitief (to)?',
+			notes: `
+			Sommige werkwoorden worden gevolgd door **-ing**, andere door **to + werkwoord**.
+
+			| + -ing | + to |
+			|---|---|
+			| enjoy, finish, mind, avoid, suggest, keep, practise, miss, can't stand | want, decide, hope, plan, promise, refuse, learn, need, would like, afford |
+
+			- *I enjoy **swimming**.* (niet ~~enjoy to swim~~)
+			- *I decided **to leave**.*
+
+			Na een **voorzetsel** altijd **-ing**: *I'm good **at cooking**. Thanks **for helping**. I look forward **to seeing** you.*
+
+			Betekenisverschil: *I **stopped smoking*** (ik rook niet meer) vs. *I **stopped to smoke*** (ik stopte om te roken).
+			*Remember **to lock** the door* (vergeet het niet) vs. *I remember **locking** it* (ik weet nog dat ik het deed).
+		`,
+			words: `
+			enjoy | genieten van
+			finish | afmaken
+			avoid | vermijden
+			suggest | voorstellen
+			mind | het erg vinden
+			decide | besluiten
+			hope | hopen
+			refuse | weigeren
+			afford | zich kunnen veroorloven
+			look forward to | uitkijken naar
+			be good at | goed zijn in
+			can't stand | niet kunnen uitstaan
+		`,
+			sentences: `
+			I enjoy reading in bed. | Ik lees graag in bed.
+			She decided to quit her job. | Ze besloot haar baan op te zeggen.
+			Do you mind closing the window? | Vind je het erg om het raam dicht te doen?
+			I'm looking forward to seeing you. | Ik kijk ernaar uit je te zien.
+			He's really good at drawing. | Hij is echt goed in tekenen.
+			We can't afford to buy a house. | We kunnen ons geen huis veroorloven.
+			I can't stand waiting. | Ik kan niet tegen wachten.
+		`,
+			drills: `
+			I enjoy ___. (cook) | cooking | to cook; cook; cooked
+			She wants ___ a doctor. (become) | to become | becoming; become; to becoming
+			I look forward to ___ you. | seeing | see; to see; saw | To is hier een voorzetsel.
+			He refused ___. (pay) | to pay | paying; pay; to paying
+			Would you mind ___ the door? | opening | to open; open; opened
+			I stopped ___. (ik rook niet meer) | smoking | to smoke; smoke; smoked
+		`
+		}),
+		lesson({
+			id: 'en-reported',
+			title: 'She said that…',
+			summary: 'Indirecte rede',
+			notes: `
+			Na **said / told** schuift de tijd meestal een stap terug:
+
+			| direct | indirect |
+			|---|---|
+			| "I **am** tired." | She said (that) she **was** tired. |
+			| "I **work** here." | He said he **worked** there. |
+			| "I **will** help." | He said he **would** help. |
+			| "I **can** come." | She said she **could** come. |
+			| "I **saw** it." | He said he **had seen** it. |
+
+			**say** vs **tell**: *tell* heeft een persoon nodig: *She **told me** that…* / *She **said** that…* (niet ~~said me~~).
+
+			Vragen: *He asked **where I lived*** (geen vraagvolgorde!), *She asked **if/whether** I was coming*.
+			Opdrachten: *He told me **to wait***.
+		`,
+			words: `
+			say | zeggen
+			said | zei
+			tell | vertellen; zeggen (tegen)
+			told | vertelde
+			ask | vragen
+			whether | of
+			explain | uitleggen
+			reply | antwoorden
+			mention | noemen
+			admit | toegeven
+		`,
+			sentences: `
+			She said she was tired. | Ze zei dat ze moe was.
+			He told me he would call. | Hij zei tegen me dat hij zou bellen.
+			They asked where we lived. | Ze vroegen waar we woonden.
+			She asked if I wanted coffee. | Ze vroeg of ik koffie wilde.
+			My boss told me to wait. | Mijn baas zei dat ik moest wachten.
+			He admitted that he had lied. | Hij gaf toe dat hij had gelogen.
+		`,
+			drills: `
+			She ___ me that she was busy. | told | said; say; talked
+			He ___ that he was busy. | said | told; told me to; says me
+			"I'm hungry." → She said she ___ hungry. | was | is; were; has been
+			Hij vroeg waar ik woonde: | He asked where I lived. | He asked where did I live.; He asked where do I live.; He asked me where lived I.
+			"Wait!" → He told me ___. | to wait | wait; waiting; that wait
+		`
+		})
+	]
+);

src/lib/language-learner/courses/en/b2.ts

@@ -0,0 +1,347 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b2',
+	'B2',
+	'Upper intermediate',
+	'Third conditional, modal perfects, wensen, verbindingswoorden, valse vrienden en idioom.',
+	[
+		lesson({
+			id: 'en-third-conditional',
+			title: 'If I had known…',
+			summary: 'Third conditional en mixed conditionals',
+			notes: `
+			### Third conditional — denkbeeldig verleden
+			**If + past perfect, would have + voltooid deelwoord**
+			*If I **had known**, I **would have come**.* — Als ik het had geweten, was ik gekomen.
+
+			In spreektaal: *If I'd known, I'd have come.* (Let op: *'d* = *had* na *if*, *would* in de hoofdzin.)
+
+			### Mixed conditional — verleden oorzaak, gevolg nu
+			*If I **had taken** that job, I **would be** rich now.*
+
+			Nooit *would* in de if-zin: ~~If I would have known~~.
+		`,
+			words: `
+			would have | zou hebben
+			could have | had kunnen
+			might have | had misschien
+			if only | had ik maar
+			regret | spijt hebben van
+			otherwise | anders
+			chance | kans
+			accept | accepteren; aannemen
+		`,
+			sentences: `
+			If I had known, I would have come. | Als ik het had geweten, was ik gekomen.
+			If we had left earlier, we wouldn't have missed the train. | Als we eerder waren vertrokken, hadden we de trein niet gemist.
+			She would have passed if she had studied. | Ze was geslaagd als ze had gestudeerd.
+			If I had accepted that job, I would live in London now. | Als ik die baan had aangenomen, zou ik nu in Londen wonen.
+			What would you have done? | Wat zou jij hebben gedaan?
+		`,
+			drills: `
+			If I ___ the answer, I would have told you. | had known | would have known; knew; have known
+			If she had asked, I ___ her. | would have helped | would help; had helped; will have helped
+			Als ik het had geweten…: | If I had known… | If I would have known…; If I knew…; If I have known…
+			If I had studied medicine, I ___ a doctor now. | would be | would have been; will be; had been | Mixed: verleden oorzaak, gevolg nu.
+		`
+		}),
+		lesson({
+			id: 'en-modal-perfect',
+			title: 'You should have told me',
+			summary: 'Should have, must have, could have',
+			notes: `
+			**Modaal werkwoord + have + voltooid deelwoord** gaat over het verleden:
+
+			| | betekenis | voorbeeld |
+			|---|---|---|
+			| should have | had moeten (maar niet gedaan) | *You **should have told** me.* |
+			| shouldn't have | had niet moeten | *I **shouldn't have eaten** so much.* |
+			| must have | moet wel (zeker) | *She **must have forgotten**.* |
+			| can't have | kan niet (onmogelijk) | *He **can't have seen** it.* |
+			| could have | had gekund | *We **could have won**.* |
+			| might / may have | misschien | *They **might have left** already.* |
+
+			Gesproken klinkt *should have* als "should've" — schrijf **nooit** ~~should of~~.
+		`,
+			words: `
+			should have | had moeten
+			must have | moet wel hebben
+			can't have | kan niet hebben
+			could have | had kunnen
+			might have | zou kunnen hebben
+			forget | vergeten
+			notice | opmerken
+			mistake | fout
+			apologise | zich verontschuldigen
+		`,
+			sentences: `
+			You should have told me earlier. | Je had het me eerder moeten vertellen.
+			I shouldn't have said that. | Dat had ik niet moeten zeggen.
+			She must have missed the bus. | Ze heeft vast de bus gemist.
+			He can't have finished already. | Hij kan nog niet klaar zijn.
+			We could have won the match. | We hadden de wedstrijd kunnen winnen.
+			They might have got lost. | Misschien zijn ze verdwaald.
+		`,
+			drills: `
+			Je had het moeten zeggen: | You should have said it. | You should said it.; You should of said it.; You must have said it.
+			The lights are off. They ___ gone out. (zeker) | must have | should have; can't have; must
+			He ___ stolen it; he was with me all day. | can't have | must have; shouldn't have; mustn't have
+			I'm so full. I ___ eaten that cake. | shouldn't have | mustn't have; can't have; shouldn't
+		`
+		}),
+		lesson({
+			id: 'en-phrasal-2',
+			title: 'Put up with it',
+			summary: 'Gevorderde phrasal verbs',
+			notes: `
+			| phrasal verb | betekenis |
+			|---|---|
+			| put up with | tolereren, pikken |
+			| come up with | bedenken |
+			| look forward to | uitkijken naar |
+			| get along with | goed kunnen opschieten met |
+			| run into | tegen het lijf lopen |
+			| turn down | afwijzen; zachter zetten |
+			| carry on | doorgaan |
+			| figure out | uitvogelen |
+			| bring up | ter sprake brengen; opvoeden |
+			| put off | uitstellen |
+			| set up | opzetten, oprichten |
+			| break down | kapotgaan; instorten |
+			| work out | sporten; uitwerken, goed aflopen |
+			| call off | afgelasten |
+			| look into | onderzoeken |
+		`,
+			words: `
+			put up with | tolereren; verdragen
+			come up with | bedenken
+			get along with | goed kunnen opschieten met
+			run into | tegen het lijf lopen
+			turn down | afwijzen; zachter zetten
+			carry on | doorgaan
+			figure out | uitvogelen
+			bring up | ter sprake brengen; opvoeden
+			put off | uitstellen
+			set up | opzetten; oprichten
+			break down | kapotgaan
+			work out | sporten; goed aflopen
+			call off | afgelasten
+			look into | onderzoeken
+		`,
+			sentences: `
+			I can't put up with this noise any longer. | Ik kan dit lawaai niet langer verdragen.
+			She came up with a brilliant idea. | Ze bedacht een briljant idee.
+			Do you get along with your colleagues? | Kun je goed opschieten met je collega's?
+			I ran into an old friend yesterday. | Ik kwam gisteren een oude vriend tegen.
+			They turned down my offer. | Ze wezen mijn aanbod af.
+			Stop putting it off and just do it. | Stop met uitstellen en doe het gewoon.
+			The match was called off because of the rain. | De wedstrijd werd afgelast vanwege de regen.
+			Don't worry, it'll all work out. | Maak je geen zorgen, het komt allemaal goed.
+		`,
+			drills: `
+			bedenken: come up ___ | with | to; for; on
+			The meeting was called ___. (afgelast) | off | out; down; away
+			I can't put up ___ him anymore. | with | on; for; to
+			Stop putting ___ your homework! (uitstellen) | off | away; down; out
+			We'll look ___ the problem. (onderzoeken) | into | after; for; out
+			My car broke ___ on the motorway. | down | up; off; out
+		`
+		}),
+		lesson({
+			id: 'en-wish',
+			title: 'I wish I could',
+			summary: 'Wish en if only',
+			notes: `
+			| wens over | vorm | voorbeeld |
+			|---|---|---|
+			| het heden | wish + past simple | *I wish I **had** more time.* — Had ik maar meer tijd. |
+			| het verleden (spijt) | wish + past perfect | *I wish I **had studied** harder.* |
+			| irritatie over een ander | wish + would | *I wish you **would stop** talking.* |
+			| een vaardigheid | wish + could | *I wish I **could** sing.* |
+
+			**If only** is sterker: *If only I **were** taller!*
+			Niet: ~~I wish I have~~ of ~~I wish I would have~~.
+		`,
+			words: `
+			wish | wensen
+			if only | had … maar; als … maar
+			regret | spijt
+			instead | in plaats daarvan
+			complain | klagen
+			patient | geduldig
+		`,
+			sentences: `
+			I wish I had more free time. | Had ik maar meer vrije tijd.
+			I wish I hadn't said that. | Had ik dat maar niet gezegd.
+			I wish you would listen to me. | Ik wou dat je naar me luisterde.
+			I wish I could speak Korean. | Kon ik maar Koreaans spreken.
+			If only I had known! | Had ik het maar geweten!
+			She wishes she lived by the sea. | Ze zou willen dat ze aan zee woonde.
+		`,
+			drills: `
+			I wish I ___ taller. | were | am; will be; would be
+			I wish I ___ that film. (spijt, gezien) | hadn't watched | didn't watch; haven't watched; wouldn't watch
+			I wish it ___ raining! (irritatie) | would stop | stops; stopped to; will stop
+			Had ik maar meer geld: | I wish I had more money. | I wish I have more money.; I wish I would have more money.; I wish I had had more money now.
+		`
+		}),
+		lesson({
+			id: 'en-linking',
+			title: 'However, although, despite',
+			summary: 'Verbindingswoorden',
+			notes: `
+			| | + | voorbeeld |
+			|---|---|---|
+			| although / even though | een bijzin | *Although it rained, we went out.* |
+			| despite / in spite of | zelfstandig naamwoord of -ing | *Despite the rain, we went out.* |
+			| however | nieuwe zin, met komma | *It rained. However, we went out.* |
+			| whereas / while | contrast tussen twee dingen | *I like tea, whereas she prefers coffee.* |
+			| therefore / as a result | gevolg | *It rained. Therefore, the match was cancelled.* |
+			| moreover / furthermore / in addition | toevoeging (formeel) | |
+			| due to / because of | oorzaak + zelfst. nw. | *due to the weather* |
+
+			Fout: ~~Despite it rained~~ → *Despite **the rain*** of *Despite **the fact that** it rained*.
+		`,
+			words: `
+			although | hoewel
+			even though | ook al
+			despite | ondanks
+			in spite of | ondanks
+			however | echter
+			whereas | terwijl (contrast)
+			therefore | daarom
+			moreover | bovendien
+			furthermore | verder; bovendien
+			due to | vanwege; als gevolg van
+			on the other hand | aan de andere kant
+			nevertheless | niettemin
+		`,
+			sentences: `
+			Although it was cold, we went swimming. | Hoewel het koud was, gingen we zwemmen.
+			Despite the rain, the concert went ahead. | Ondanks de regen ging het concert door.
+			The hotel was nice. However, it was expensive. | Het hotel was mooi. Het was echter duur.
+			I love cities, whereas my partner prefers the countryside. | Ik hou van steden, terwijl mijn partner het platteland verkiest.
+			The flight was cancelled due to fog. | De vlucht werd geannuleerd vanwege mist.
+			He was tired; nevertheless, he kept working. | Hij was moe; toch bleef hij doorwerken.
+		`,
+			drills: `
+			___ the traffic, we arrived on time. | Despite | Although; However; Even though
+			___ it was late, she kept working. | Although | Despite; However; In spite of
+			It was cheap. ___, it broke after a week. | However | Although; Despite; Whereas
+			ondanks dat het regende: | despite the fact that it rained | despite it rained; despite of the rain; in spite it rained
+			The game was cancelled ___ the storm. | due to | because; although; despite
+		`
+		}),
+		lesson({
+			id: 'en-false-friends',
+			title: 'False friends',
+			summary: 'Valse vrienden tussen Nederlands en Engels',
+			notes: `
+			| Engels | betekent | Nederlands woord dat erop lijkt | = in het Engels |
+			|---|---|---|---|
+			| eventually | uiteindelijk | eventueel | possibly, if necessary |
+			| actually | eigenlijk, in feite | actueel | current, topical |
+			| sympathetic | meelevend | sympathiek | likeable, nice |
+			| brave | dapper | braaf | good, well-behaved |
+			| become | worden | bekomen | recover |
+			| control | beheersen | controleren | check |
+			| familiar | bekend, vertrouwd | familie | family, relatives |
+			| sensible | verstandig | sensibel | sensitive |
+			| chef | kok | chef | boss, manager |
+			| genial | vriendelijk, joviaal | geniaal | brilliant |
+			| undertaker | begrafenisondernemer | ondernemer | entrepreneur |
+			| fabric | stof (textiel) | fabriek | factory |
+			| customer | klant | kostuum | costume, suit |
+			| kind | aardig | kind | child |
+		`,
+			words: `
+			eventually | uiteindelijk
+			possibly | eventueel; mogelijk
+			actually | eigenlijk
+			current | actueel; huidig
+			sympathetic | meelevend
+			likeable | sympathiek
+			brave | dapper
+			well-behaved | braaf
+			check | controleren
+			familiar | vertrouwd; bekend
+			relatives | familie(leden)
+			sensible | verstandig
+			sensitive | gevoelig; sensibel
+			boss | chef; baas
+			factory | fabriek
+			brilliant | geniaal
+		`,
+			sentences: `
+			Eventually, we found the hotel. | Uiteindelijk vonden we het hotel.
+			We could possibly meet tomorrow. | We kunnen eventueel morgen afspreken.
+			Actually, I don't like coffee. | Eigenlijk hou ik niet van koffie.
+			Can you check the numbers? | Kun jij de cijfers controleren?
+			He's a very likeable guy. | Hij is een heel sympathieke gozer.
+			That's a very sensible decision. | Dat is een heel verstandig besluit.
+			She was very brave. | Ze was heel dapper.
+			I'm visiting relatives this weekend. | Ik ga dit weekend bij familie op bezoek.
+		`,
+			drills: `
+			eventueel: | possibly | eventually; actual; eventual
+			uiteindelijk: | eventually | possibly; actually; actual
+			controleren: | check | control; controle; test out
+			Hij is heel sympathiek: | He's very likeable. | He's very sympathetic.; He's very sympathic.; He's very brave.
+			een verstandige keuze: | a sensible choice | a sensitive choice; a sensibel choice; a sense choice
+			Ik ga naar mijn familie: | I'm visiting relatives. | I'm visiting my familiars.; I'm visiting my family's.; I'm visiting familiar.
+		`
+		}),
+		lesson({
+			id: 'en-idioms-1',
+			title: 'Piece of cake',
+			summary: 'Veelgebruikte Engelse uitdrukkingen',
+			notes: `
+			| idioom | betekenis | Nederlands |
+			|---|---|---|
+			| a piece of cake | heel makkelijk | een fluitje van een cent |
+			| it's raining cats and dogs | het giet | het regent pijpenstelen |
+			| break the ice | de spanning breken | het ijs breken |
+			| under the weather | niet lekker | niet lekker in je vel |
+			| hit the nail on the head | precies goed | de spijker op zijn kop slaan |
+			| cost an arm and a leg | peperduur | een rib uit je lijf |
+			| once in a blue moon | zelden | eens in de zoveel tijd |
+			| let the cat out of the bag | een geheim verklappen | je mond voorbij praten |
+			| the ball is in your court | jij bent aan zet | de bal ligt bij jou |
+			| call it a day | ermee stoppen voor vandaag | het voor gezien houden |
+			| pull someone's leg | iemand plagen | iemand in de maling nemen |
+			| on the fence | twijfelen | op twee gedachten hinken |
+		`,
+			words: `
+			a piece of cake | een fluitje van een cent
+			raining cats and dogs | regent pijpenstelen
+			break the ice | het ijs breken
+			under the weather | niet lekker; grieperig
+			hit the nail on the head | de spijker op zijn kop slaan
+			cost an arm and a leg | een rib uit je lijf kosten
+			once in a blue moon | zelden
+			let the cat out of the bag | een geheim verklappen
+			call it a day | ermee ophouden (voor vandaag)
+			pull someone's leg | iemand in de maling nemen
+			on the fence | twijfelen
+			the ball is in your court | jij bent aan zet
+		`,
+			sentences: `
+			The exam was a piece of cake. | Het examen was een fluitje van een cent.
+			I'm feeling a bit under the weather. | Ik voel me een beetje niet lekker.
+			That car must have cost an arm and a leg. | Die auto moet een rib uit je lijf hebben gekost.
+			I only see him once in a blue moon. | Ik zie hem maar zelden.
+			It's late, let's call it a day. | Het is laat, laten we ermee stoppen.
+			Are you pulling my leg? | Neem je me in de maling?
+			You hit the nail on the head. | Je slaat de spijker op zijn kop.
+		`,
+			drills: `
+			Heel makkelijk: a piece of ___ | cake | pie; bread; biscuit
+			Het regent pijpenstelen: it's raining ___ | cats and dogs | pipes and stems; buckets and dogs; cows and horses
+			Peperduur: it cost an arm and a ___ | leg | foot; hand; head
+			Zelden: once in a ___ moon | blue | full; red; silver
+			Een geheim verklappen: let the ___ out of the bag | cat | dog; cake; secret
+		`
+		})
+	]
+);

src/lib/language-learner/courses/en/c1.ts

@@ -0,0 +1,318 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'c1',
+	'C1',
+	'Advanced',
+	'Inversie, cleft sentences, formeel register, collocaties en lastige woordparen.',
+	[
+		lesson({
+			id: 'en-inversion',
+			title: 'Never have I…',
+			summary: 'Inversie voor nadruk',
+			notes: `
+			Na een **ontkennende of beperkende** uitdrukking aan het begin van de zin draait de volgorde om, zoals in een vraag:
+
+			| begin | voorbeeld |
+			|---|---|
+			| Never | ***Never have I seen** such chaos.* |
+			| Rarely / Seldom | ***Rarely does he** complain.* |
+			| Not only | ***Not only did she** win, but she also broke the record.* |
+			| Hardly … when | ***Hardly had we** arrived when it started to rain.* |
+			| No sooner … than | ***No sooner had I** sat down than the phone rang.* |
+			| Under no circumstances | ***Under no circumstances should you** open this.* |
+			| Only then / Only when | ***Only then did I** realise my mistake.* |
+			| Little | ***Little did they** know…* |
+
+			Conditionals zonder *if*: ***Had I** known… = If I had known… / **Should you** need help… / **Were I** you…*
+		`,
+			words: `
+			never have I | nooit heb ik
+			rarely | zelden
+			seldom | zelden
+			not only … but also | niet alleen … maar ook
+			hardly … when | nauwelijks … of
+			no sooner … than | nauwelijks … of
+			under no circumstances | onder geen enkele voorwaarde
+			only then | pas toen
+			little did I know | ik had geen idee
+			should you | mocht je
+		`,
+			sentences: `
+			Never have I seen such a beautiful sunset. | Nog nooit heb ik zo'n mooie zonsondergang gezien.
+			Not only is he rude, but he's also lazy. | Hij is niet alleen onbeleefd, maar ook lui.
+			No sooner had I left than it started raining. | Ik was nog niet weg of het begon te regenen.
+			Under no circumstances should you open the door. | Onder geen beding mag je de deur openen.
+			Little did I know what was about to happen. | Ik had geen idee wat er ging gebeuren.
+			Should you need any help, please let me know. | Mocht je hulp nodig hebben, laat het me dan weten.
+			Had I known, I would have called. | Had ik het geweten, dan had ik gebeld.
+		`,
+			drills: `
+			Never ___ such a mess. | have I seen | I have seen; I saw; seen I have
+			Rarely ___ late. | does she arrive | she arrives; arrives she; she does arrive
+			Not only ___ the exam, but she also got top marks. | did she pass | she passed; passed she; she did pass
+			___ you have any questions, call me. (Mocht) | Should | Would; If should; Shall
+			___ I known, I would have helped. | Had | If; Have; Would
+		`
+		}),
+		lesson({
+			id: 'en-cleft',
+			title: 'What I need is…',
+			summary: 'Cleft sentences voor nadruk',
+			notes: `
+			Een **cleft sentence** splitst een zin om één deel te benadrukken:
+
+			- **It**-cleft: ***It was** Tom **who** broke it.* (niet iemand anders)
+			- **What**-cleft: ***What I need is** a holiday.*
+			- **All**-cleft: ***All I want is** some peace.* — Het enige wat ik wil…
+			- **The reason why**: ***The reason why** I left **is that** …*
+			- **The thing is**: ***The thing is**, I'm broke.*
+
+			Handig in het Engels, omdat je (anders dan in het Nederlands) de woordvolgorde niet vrij kunt omgooien voor nadruk.
+		`,
+			words: `
+			it was … who | het was … die
+			what I need is | wat ik nodig heb is
+			all I want is | het enige wat ik wil is
+			the reason why | de reden waarom
+			the thing is | het punt is
+			the last thing | het laatste
+			what happened was | wat er gebeurde was
+		`,
+			sentences: `
+			It was Sarah who called, not Emma. | Het was Sarah die belde, niet Emma.
+			What I really need is a long holiday. | Wat ik echt nodig heb is een lange vakantie.
+			All I want is a cup of tea. | Het enige wat ik wil is een kopje thee.
+			The reason why I'm late is that the train was cancelled. | De reden dat ik te laat ben, is dat de trein uitviel.
+			The thing is, I don't have enough money. | Het punt is, ik heb niet genoeg geld.
+			It wasn't until midnight that he arrived. | Hij kwam pas om middernacht aan.
+		`,
+			drills: `
+			___ I need is some sleep. | What | That; Which; It
+			It was my brother ___ told me. | who | which; what; whom he
+			___ I want is to go home. (Het enige) | All | What only; Only; The all
+			It wasn't until Friday ___ I heard the news. | that | when; than; which
+		`
+		}),
+		lesson({
+			id: 'en-formal',
+			title: 'Formal register',
+			summary: 'Formeel en academisch Engels',
+			notes: `
+			| informeel | formeel |
+			|---|---|
+			| get | obtain, receive |
+			| ask for | request |
+			| find out | discover, ascertain |
+			| help | assist |
+			| need | require |
+			| start | commence |
+			| end | terminate, conclude |
+			| enough | sufficient |
+			| buy | purchase |
+			| but | however |
+			| so | therefore, consequently |
+			| a lot of | a considerable amount of, numerous |
+
+			Formeel schrijven vermijdt **afkortingen** (*don't → do not*), gebruikt vaker de **passief** en onpersoonlijke constructies: *It is recommended that…*, *It should be noted that…*
+
+			Brieven: *Dear Sir or Madam, … Yours faithfully* (naam onbekend) / *Dear Ms Smith, … Yours sincerely* (naam bekend).
+		`,
+			words: `
+			obtain | verkrijgen
+			request | verzoeken; verzoek
+			assist | assisteren; helpen
+			require | vereisen
+			commence | aanvangen
+			conclude | besluiten; afronden
+			sufficient | voldoende
+			purchase | aanschaffen; aankoop
+			consequently | bijgevolg
+			numerous | talrijk
+			regarding | betreffende
+			hereby | hierbij
+			enclosed | bijgevoegd
+			yours faithfully | hoogachtend
+		`,
+			sentences: `
+			I am writing to request further information. | Ik schrijf u om nadere informatie te vragen.
+			Please find enclosed a copy of my CV. | Bijgevoegd vindt u een kopie van mijn cv.
+			Applicants are required to have a valid passport. | Kandidaten moeten in het bezit zijn van een geldig paspoort.
+			It should be noted that the results are preliminary. | Er moet worden opgemerkt dat de resultaten voorlopig zijn.
+			Consequently, the project was postponed. | Bijgevolg werd het project uitgesteld.
+			I look forward to hearing from you. | Ik zie uw reactie met belangstelling tegemoet.
+		`,
+			drills: `
+			Formal "buy": | purchase | get; shop; grab
+			Formal "help": | assist | help out; lend a hand; give a hand
+			Formal "enough": | sufficient | plenty; loads; enough of
+			You don't know the recipient's name. End with: | Yours faithfully | Yours sincerely; Kind regards; Cheers
+			Formal "start": | commence | kick off; get going; start up
+		`
+		}),
+		lesson({
+			id: 'en-collocations',
+			title: 'Make or do?',
+			summary: 'Collocaties: woorden die bij elkaar horen',
+			notes: `
+			### make vs do
+			| make | do |
+			|---|---|
+			| a mistake, a decision, a phone call | homework, the dishes, the shopping |
+			| money, progress, an effort, noise | business, a favour, your best |
+			| friends, a mess, sense | research, damage, exercise |
+
+			### Andere vaste combinaties
+			- **heavy** rain / traffic (niet ~~strong rain~~)
+			- **strong** coffee / wind (niet ~~heavy coffee~~)
+			- **take** a photo / a break / a decision (BrE ook: make)
+			- **pay** attention / a visit / a compliment
+			- **catch** a cold / a bus
+			- **keep** a promise / a secret
+			- **commit** a crime
+			- **raise** a question / children
+		`,
+			words: `
+			make a mistake | een fout maken
+			make a decision | een besluit nemen
+			make an effort | moeite doen
+			do homework | huiswerk maken
+			do the dishes | afwassen
+			do someone a favour | iemand een plezier doen
+			heavy rain | zware regen
+			heavy traffic | druk verkeer
+			strong coffee | sterke koffie
+			take a break | pauze nemen
+			pay attention | opletten
+			catch a cold | verkouden worden
+			keep a promise | een belofte houden
+			commit a crime | een misdaad plegen
+		`,
+			sentences: `
+			Everyone makes mistakes. | Iedereen maakt fouten.
+			Could you do me a favour? | Zou je me een plezier willen doen?
+			I have to do the shopping. | Ik moet boodschappen doen.
+			There was heavy traffic on the motorway. | Er was druk verkeer op de snelweg.
+			Let's take a short break. | Laten we een korte pauze nemen.
+			Please pay attention. | Let alsjeblieft op.
+			She always keeps her promises. | Ze houdt zich altijd aan haar beloftes.
+		`,
+			drills: `
+			___ a mistake | make | do; take; have
+			___ your homework | do | make; take; have
+			___ rain | heavy | strong; big; hard
+			___ coffee | strong | heavy; hard; big
+			___ someone a favour | do | make; give; take
+			___ attention | pay | give; make; take
+			___ progress | make | do; get; take
+		`
+		}),
+		lesson({
+			id: 'en-idioms-2',
+			title: 'Beat around the bush',
+			summary: 'Gevorderde uitdrukkingen',
+			notes: `
+			| idioom | betekenis |
+			|---|---|
+			| beat around the bush | eromheen draaien |
+			| bite off more than you can chew | te veel hooi op je vork nemen |
+			| cut corners | de kantjes eraf lopen |
+			| get the ball rolling | de bal aan het rollen brengen |
+			| a blessing in disguise | een geluk bij een ongeluk |
+			| the elephant in the room | het probleem waar niemand over begint |
+			| jump on the bandwagon | op de trein springen, meedoen met een trend |
+			| miss the boat | de boot missen |
+			| sit on the fence | de kat uit de boom kijken |
+			| a storm in a teacup | een storm in een glas water |
+			| go the extra mile | een stapje extra zetten |
+			| spill the beans | een geheim verklappen |
+		`,
+			words: `
+			beat around the bush | eromheen draaien
+			bite off more than you can chew | te veel hooi op je vork nemen
+			cut corners | de kantjes eraf lopen
+			get the ball rolling | de bal aan het rollen brengen
+			a blessing in disguise | een geluk bij een ongeluk
+			the elephant in the room | het heikele onderwerp dat iedereen negeert
+			jump on the bandwagon | met de massa meedoen
+			miss the boat | de boot missen
+			a storm in a teacup | een storm in een glas water
+			go the extra mile | een stapje extra zetten
+			spill the beans | alles verklappen
+		`,
+			sentences: `
+			Stop beating around the bush and tell me. | Stop met eromheen draaien en vertel het me.
+			I think I've bitten off more than I can chew. | Ik denk dat ik te veel hooi op mijn vork heb genomen.
+			Losing that job was a blessing in disguise. | Die baan verliezen was een geluk bij een ongeluk.
+			It was just a storm in a teacup. | Het was gewoon een storm in een glas water.
+			She always goes the extra mile for her clients. | Ze zet altijd een stapje extra voor haar klanten.
+			Come on, spill the beans! | Kom op, vertel!
+			Let's get the ball rolling. | Laten we beginnen.
+		`,
+			drills: `
+			Een storm in een glas water: a storm in a ___ | teacup | glass of water; bathtub; coffee cup
+			Te veel hooi op je vork: bite off more than you can ___ | chew | eat; swallow; carry
+			De kantjes eraf lopen: cut ___ | corners | edges; sides; the edges off
+			Eromheen draaien: beat around the ___ | bush | tree; house; hedge
+			Een geluk bij een ongeluk: a blessing in ___ | disguise | the dark; hiding; secret
+		`
+		}),
+		lesson({
+			id: 'en-tricky',
+			title: 'Affect or effect?',
+			summary: 'Woordparen die zelfs moedertaalsprekers verwarren',
+			notes: `
+			| | |
+			|---|---|
+			| **affect** (ww.) — beïnvloeden | **effect** (znw.) — gevolg |
+			| **lie** (lay, lain) — liggen | **lay** (laid, laid) — leggen |
+			| **fewer** — telbaar | **less** — ontelbaar |
+			| **its** — zijn/haar | **it's** — it is |
+			| **their** — hun / **there** — daar | **they're** — they are |
+			| **then** — dan, toen | **than** — dan (vergelijking) |
+			| **lose** — verliezen | **loose** — los |
+			| **advice** (znw.) — advies | **advise** (ww.) — adviseren |
+			| **who** — onderwerp | **whom** — lijdend voorwerp (formeel) |
+			| **borrow** — lenen van | **lend** — lenen aan |
+			| **rise** — stijgen (zelf) | **raise** — verhogen (iets) |
+
+			Typische Nederlandse fouten: ~~I am agree~~ → *I **agree***, ~~Can you lend me your pen?~~ is goed, ~~Can I lend your pen?~~ → *Can I **borrow** your pen?*
+		`,
+			words: `
+			affect | beïnvloeden
+			effect | effect; gevolg
+			lie | liggen; liegen
+			lay | leggen
+			fewer | minder (telbaar)
+			less | minder (ontelbaar)
+			lose | verliezen
+			loose | los; wijd
+			advise | adviseren
+			borrow | lenen (van iemand)
+			lend | uitlenen (aan iemand)
+			rise | stijgen
+			raise | verhogen; opheffen
+			agree | het eens zijn
+		`,
+			sentences: `
+			The weather affects my mood. | Het weer beïnvloedt mijn humeur.
+			The medicine had no effect. | Het medicijn had geen effect.
+			Can I borrow your pen? | Mag ik je pen lenen?
+			Could you lend me ten euros? | Kun je me tien euro lenen?
+			I agree with you. | Ik ben het met je eens.
+			Prices have risen sharply. | De prijzen zijn sterk gestegen.
+			They raised their prices. | Ze hebben hun prijzen verhoogd.
+			Don't lose your keys. | Raak je sleutels niet kwijt.
+		`,
+			drills: `
+			Stress can ___ your health. | affect | effect; infect; afect
+			It had a big ___ on me. | effect | affect; affection; efect
+			Ik ben het met je eens: | I agree with you. | I am agree with you.; I agree to you.; I'm agreeing you.
+			Can I ___ your car? (lenen van jou) | borrow | lend; loan; lent
+			___ people came than expected. | Fewer | Less; Lesser; Fewest
+			The dog wagged ___ tail. | its | it's; his; their
+			Prices ___ every year. | rise | raise; arise; rises
+		`
+		})
+	]
+);

src/lib/language-learner/courses/en/index.ts

@@ -0,0 +1,18 @@
+import { course } from '../../course';
+import a1 from './a1';
+import a2 from './a2';
+import b1 from './b1';
+import b2 from './b2';
+import c1 from './c1';
+
+export default course(
+	{
+		code: 'en',
+		name: 'English',
+		nativeName: 'English',
+		glossLang: 'nl',
+		voice: 'en-GB',
+		tagline: 'Van de basis tot vloeiend Engels, uitgelegd in het Nederlands.'
+	},
+	[a1, a2, b1, b2, c1]
+);

src/lib/language-learner/courses/index.ts

@@ -0,0 +1,48 @@
+import type { Course, LangCode } from '../types';
+
+export type CourseInfo = {
+	code: LangCode;
+	name: string;
+	nativeName: string;
+	tagline: string;
+	glossLang: LangCode;
+};
+
+/** Lightweight metadata; the full course is loaded on demand. */
+export const COURSES: CourseInfo[] = [
+	{
+		code: 'nl',
+		name: 'Dutch',
+		nativeName: 'Nederlands',
+		tagline: 'From "hallo" to reading the news, taught in English.',
+		glossLang: 'en'
+	},
+	{
+		code: 'ko',
+		name: 'Korean',
+		nativeName: '한국어',
+		tagline: 'Hangul first, then grammar and speech levels, taught in English.',
+		glossLang: 'en'
+	},
+	{
+		code: 'en',
+		name: 'English',
+		nativeName: 'English',
+		tagline: 'Van de basis tot vloeiend Engels, uitgelegd in het Nederlands.',
+		glossLang: 'nl'
+	}
+];
+
+export const isLang = (value: string): value is LangCode => COURSES.some((c) => c.code === value);
+
+export const courseInfo = (code: LangCode) => COURSES.find((c) => c.code === code)!;
+
+const loaders: Record<LangCode, () => Promise<{ default: Course }>> = {
+	nl: () => import('./nl'),
+	ko: () => import('./ko'),
+	en: () => import('./en')
+};
+
+export async function loadCourse(code: LangCode): Promise<Course> {
+	return (await loaders[code]()).default;
+}

src/lib/language-learner/courses/ko/a1.ts

@@ -0,0 +1,465 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a1',
+	'A1',
+	'Beginner',
+	'Greetings, introductions, numbers, particles and your first verbs.',
+	[
+		lesson({
+			id: 'ko-greetings',
+			title: '안녕하세요',
+			summary: 'Greetings, thanks and apologies',
+			notes: `
+			Korean has **speech levels**. This course starts with the polite **해요체** (ending in **-요**), which is safe with almost anyone.
+
+			**안녕하세요** literally asks "are you at peace?" and works any time of day.
+
+			### Two ways to say goodbye
+			- **안녕히 가세요** — "go in peace": say it to the person **leaving**.
+			- **안녕히 계세요** — "stay in peace": say it to the person **staying** (when you leave).
+
+			Thanks: **감사합니다** (a bit more formal) and **고맙습니다** are both fine. **고마워요** is softer.
+			Sorry: **죄송합니다** (formal, serious), **미안해요** (polite, lighter).
+		`,
+			words: `
+			안녕하세요 | hello
+			안녕히 가세요 | goodbye (to someone leaving)
+			안녕히 계세요 | goodbye (to someone staying)
+			감사합니다 | thank you
+			고맙습니다 | thank you
+			죄송합니다 | I'm sorry (formal)
+			미안해요 | I'm sorry
+			괜찮아요 | it's okay; I'm fine
+			네; 예 | yes
+			아니요 | no
+			반갑습니다 | nice to meet you
+			실례합니다 | excuse me
+			여보세요 | hello (on the phone)
+			잘 부탁드립니다 | please treat me well; I look forward to working with you
+		`,
+			sentences: `
+			안녕하세요, 반갑습니다. | Hello, nice to meet you.
+			정말 감사합니다. | Thank you very much.
+			괜찮아요? | Are you okay?
+			네, 괜찮아요. | Yes, I'm fine.
+			늦어서 죄송합니다. | I'm sorry for being late.
+			잘 부탁드립니다. | I look forward to working with you.
+		`,
+			drills: `
+			You are leaving a shop. You say to the shopkeeper: | 안녕히 계세요 | 안녕히 가세요; 안녕하세요; 여보세요 | They stay, so: stay in peace.
+			A guest leaves your home. You say: | 안녕히 가세요 | 안녕히 계세요; 반갑습니다; 실례합니다
+			You pick up the phone: | 여보세요 | 안녕히 계세요; 실례합니다; 괜찮아요
+			You bump into someone on the street: | 죄송합니다 | 감사합니다; 반갑습니다; 괜찮아요
+		`
+		}),
+		lesson({
+			id: 'ko-introductions',
+			title: '저는 학생이에요',
+			summary: 'Introducing yourself with 이에요/예요',
+			notes: `
+			### "To be": 이에요 / 예요
+			To say "X is Y", attach **이에요** after a consonant or **예요** after a vowel:
+			- 학생**이에요** — (I) am a student
+			- 의사**예요** — (I) am a doctor
+
+			The negative is **아니에요**, with **이/가** on the noun: *학생**이** 아니에요* — (I) am not a student.
+
+			### 저 and 는
+			**저** is the humble "I". **저는** = "as for me" (the **topic** particle 는). Korean often drops the subject when it's obvious.
+
+			Korean word order is **subject – object – verb**: the verb is always last.
+
+			Nationality: country + **사람**: 한국 사람, 네덜란드 사람, 영국 사람, 미국 사람.
+		`,
+			words: `
+			저 | I; me (humble)
+			이름 | name
+			학생 | student
+			선생님 | teacher
+			회사원 | office worker
+			의사 | doctor
+			사람 | person
+			나라 | country
+			네덜란드 | the Netherlands
+			미국 | the USA
+			영국 | the UK
+			어느 | which
+			뭐 | what
+			아니에요 | is not
+			이에요; 예요 | is; am; are
+		`,
+			sentences: `
+			저는 학생이에요. | I am a student.
+			이름이 뭐예요? | What is your name?
+			제 이름은 민수예요. | My name is Minsu.
+			어느 나라 사람이에요? | Where are you from? (Which country's person?)
+			저는 네덜란드 사람이에요. | I am Dutch.
+			저는 의사가 아니에요. | I'm not a doctor.
+			선생님이에요? | Are you a teacher?
+		`,
+			drills: `
+			저는 학생___. | 이에요 | 예요; 이다; 은요 | 학생 ends in a consonant.
+			저는 의사___. | 예요 | 이에요; 이예요; 가요 | 의사 ends in a vowel.
+			저는 선생님___ 아니에요. | 이 | 은; 을; 가
+			제 이름___ 지민이에요. | 은 | 는; 이; 을 | 이름 ends in a consonant: 은.
+			"Which country?" | 어느 나라 | 무슨 나라; 뭐 나라; 어디 나라
+		`
+		}),
+		lesson({
+			id: 'ko-this-that',
+			title: '이게 뭐예요?',
+			summary: 'This, that, and the topic and subject particles',
+			notes: `
+			### 이, 그, 저
+			| | near me | near you | over there |
+			|---|---|---|---|
+			| this/that + noun | 이 책 | 그 책 | 저 책 |
+			| thing | 이것 (이거) | 그것 (그거) | 저것 (저거) |
+			| place | 여기 | 거기 | 저기 |
+
+			In speech: **이게** = 이것이, **그게** = 그것이, **뭐예요** = 무엇이에요.
+
+			### 은/는 (topic) vs 이/가 (subject)
+			- **은/는** marks the **topic**, often something already known or contrasted: *저는 학생이에요.*
+			- **이/가** marks the **subject**, often new information or an answer to "who/what": *누**가** 왔어요? 민수**가** 왔어요.*
+
+			Form: **은 / 이** after a consonant, **는 / 가** after a vowel.
+
+			**제** = my (humble, from 저의). *제 책* = my book.
+		`,
+			words: `
+			이것; 이거 | this (thing)
+			그것; 그거 | that (thing, near you)
+			저것; 저거 | that (thing, over there)
+			여기 | here
+			거기 | there (near you)
+			저기 | over there
+			누구 | who
+			제 | my
+			책 | book
+			가방 | bag
+			휴대폰; 핸드폰 | mobile phone
+			시계 | watch; clock
+			우산 | umbrella
+			지갑 | wallet
+			열쇠 | key
+			친구 | friend
+		`,
+			sentences: `
+			이게 뭐예요? | What is this?
+			그건 제 가방이에요. | That is my bag.
+			저 사람은 누구예요? | Who is that person?
+			제 친구예요. | It's my friend.
+			여기가 어디예요? | Where is this place?
+			이 우산은 누구 거예요? | Whose umbrella is this?
+			그 책이 재미있어요. | That book is interesting.
+		`,
+			drills: `
+			(near you) ___ 뭐예요? | 그게 | 이게; 저게; 거기 | 그 = near the listener.
+			가방___ 어디에 있어요? | 이 | 가; 은; 을
+			친구___ 한국 사람이에요. (topic) | 는 | 은; 가; 이
+			누가 했어요? – 제 동생___ 했어요. | 이 | 은; 가; 는 | An answer to "who" takes 이/가.
+			___ 책은 제 책이에요. (this) | 이 | 이거; 여기; 이게
+		`
+		}),
+		lesson({
+			id: 'ko-sino-numbers',
+			title: '일, 이, 삼',
+			summary: 'Sino-Korean numbers: money, dates, phone numbers',
+			notes: `
+			Korean has **two** number systems. **Sino-Korean** (from Chinese) is used for:
+			money, dates, phone numbers, minutes, floors, addresses, and anything above 99.
+
+			| | | | | |
+			|---|---|---|---|---|
+			| 1 일 | 2 이 | 3 삼 | 4 사 | 5 오 |
+			| 6 육 | 7 칠 | 8 팔 | 9 구 | 10 십 |
+
+			Bigger numbers are built like a calculator: **이십삼** = 2×10+3 = 23. **백** 100, **천** 1,000, **만** 10,000.
+			No 일 before 십, 백, 천, 만: 110 = **백십**, 10,000 = **만**.
+
+			**만** trips up learners: 50,000 won is **오만 원** (5 × 10,000), 1,000,000 is **백만**.
+
+			Zero is **영** or, in phone numbers, **공**: 010-1234-5678 = 공일공 일이삼사 오육칠팔.
+
+			Dates: **년** (year), **월** (month), **일** (day): 2026년 3월 1일 = 이천이십육 년 삼월 일 일. June = **유월**, October = **시월**.
+		`,
+			words: `
+			일 | one (Sino)
+			이 | two (Sino)
+			삼 | three (Sino)
+			사 | four (Sino)
+			오 | five (Sino)
+			육 | six (Sino)
+			칠 | seven (Sino)
+			팔 | eight (Sino)
+			구 | nine (Sino)
+			십 | ten (Sino)
+			백 | hundred
+			천 | thousand
+			만 | ten thousand
+			원 | won (currency)
+			얼마 | how much
+			전화번호 | phone number
+			몇 | how many; what number
+			생일 | birthday
+		`,
+			sentences: `
+			이거 얼마예요? | How much is this?
+			만 원이에요. | It's 10,000 won.
+			삼천오백 원이에요. | It's 3,500 won.
+			전화번호가 뭐예요? | What's your phone number?
+			생일이 몇 월 며칠이에요? | When is your birthday?
+			제 생일은 유월 십일이에요. | My birthday is June 10th.
+			몇 층이에요? | Which floor is it?
+		`,
+			drills: `
+			15 (Sino) | 십오 | 일십오; 오십; 열다섯
+			300 (Sino) | 삼백 | 삼십; 삼천; 셋백
+			10,000 (Sino) | 만 | 일만천; 십천; 천
+			₩50,000 | 오만 원 | 오천 원; 오십만 원; 오백 원
+			June | 유월 | 육월; 여섯월; 유울 | 육 loses its ㄱ in 유월.
+			October | 시월 | 십월; 열월; 시울
+		`
+		}),
+		lesson({
+			id: 'ko-native-numbers',
+			title: '하나, 둘, 셋',
+			summary: 'Native Korean numbers: counting, age, hours',
+			notes: `
+			**Native Korean** numbers go from 1 to 99 and are used for **counting things**, **age** and **hours**.
+
+			| | | | | |
+			|---|---|---|---|---|
+			| 1 하나 | 2 둘 | 3 셋 | 4 넷 | 5 다섯 |
+			| 6 여섯 | 7 일곱 | 8 여덟 | 9 아홉 | 10 열 |
+
+			Tens: 20 스물, 30 서른, 40 마흔, 50 쉰, 60 예순, 70 일흔, 80 여든, 90 아흔.
+
+			### Counters
+			Korean counts with **number + counter**. Before a counter, 1–4 and 20 shorten:
+			**하나 → 한, 둘 → 두, 셋 → 세, 넷 → 네, 스물 → 스무**.
+
+			| counter | for | example |
+			|---|---|---|
+			| 개 | things | 사과 세 개 — three apples |
+			| 명 | people | 학생 두 명 — two students |
+			| 살 | age | 스무 살 — 20 years old |
+			| 시 | o'clock | 한 시 — 1 o'clock |
+			| 마리 | animals | 고양이 한 마리 — one cat |
+			| 잔 | cups | 커피 두 잔 — two coffees |
+
+			Time mixes both systems: **hours native, minutes Sino**. 3:20 = **세 시 이십 분**. Half past = **반**: 세 시 반.
+		`,
+			words: `
+			하나 | one (native)
+			둘 | two (native)
+			셋 | three (native)
+			넷 | four (native)
+			다섯 | five (native)
+			여섯 | six (native)
+			일곱 | seven (native)
+			여덟 | eight (native)
+			아홉 | nine (native)
+			열 | ten (native)
+			스물 | twenty (native)
+			개 | (counter for things)
+			명 | (counter for people)
+			살 | years old
+			시 | o'clock
+			분 | minute
+			반 | half
+			지금 | now
+		`,
+			sentences: `
+			지금 몇 시예요? | What time is it now?
+			세 시 반이에요. | It's half past three.
+			몇 살이에요? | How old are you?
+			스물다섯 살이에요. | I'm twenty-five.
+			사과 두 개 주세요. | Two apples, please.
+			가족이 몇 명이에요? | How many people are in your family?
+			커피 한 잔 주세요. | One coffee, please.
+		`,
+			drills: `
+			3 people | 세 명 | 셋 명; 삼 명; 세 개
+			2 o'clock | 두 시 | 이 시; 둘 시; 두 분
+			20 years old | 스무 살 | 스물 살; 이십 살; 스무 개
+			5:30 | 다섯 시 반 | 오 시 반; 다섯 시 삼십 시; 오 시 삼십 분
+			4 apples: 사과 ___ | 네 개 | 넷 개; 사 개; 네 명
+			10:15 | 열 시 십오 분 | 십 시 십오 분; 열 시 열다섯 분; 십 시 열다섯 분 | Hours native, minutes Sino.
+		`
+		}),
+		lesson({
+			id: 'ko-location',
+			title: '어디에 있어요?',
+			summary: '있어요 / 없어요, location words and 에',
+			notes: `
+			**있다** means both "to be (somewhere)" and "to have". **없다** is its opposite.
+			- *책이 **있어요**.* — There is a book. / I have a book.
+			- *시간이 **없어요**.* — I don't have time.
+
+			### Location: noun + 에 있어요
+			**에** marks where something is: *화장실이 어디**에** 있어요?* — Where is the bathroom?
+
+			Position words come **after** the reference noun, then 에:
+			*책상 **위에*** — on the desk, *집 **앞에*** — in front of the house.
+
+			| | |
+			|---|---|
+			| 위 | on, above |
+			| 아래 / 밑 | under |
+			| 앞 | in front |
+			| 뒤 | behind |
+			| 옆 | next to |
+			| 안 | inside |
+			| 밖 | outside |
+			| 사이 | between |
+		`,
+			words: `
+			있다 | to be (somewhere); to have
+			없다 | to not be; to not have
+			어디 | where
+			위 | top; on; above
+			아래 | under; below
+			앞 | front
+			뒤 | back; behind
+			옆 | side; next to
+			안 | inside
+			밖 | outside
+			집 | house; home
+			방 | room
+			화장실 | bathroom; toilet
+			책상 | desk
+			고양이 | cat
+			시간 | time
+		`,
+			sentences: `
+			화장실이 어디에 있어요? | Where is the bathroom?
+			책상 위에 책이 있어요. | There's a book on the desk.
+			고양이가 의자 밑에 있어요. | The cat is under the chair.
+			은행 옆에 카페가 있어요. | There's a café next to the bank.
+			저는 형이 있어요. | I have an older brother.
+			오늘은 시간이 없어요. | I don't have time today.
+			집에 아무도 없어요. | There's nobody at home.
+		`,
+			drills: `
+			The phone is on the table: 휴대폰이 테이블 ___ 있어요. | 위에 | 에 위; 위를; 앞이
+			I don't have money: 돈이 ___. | 없어요 | 안 있어요; 아니에요; 없다요 | The negative of 있다 is 없다.
+			Where is it? 어디___ 있어요? | 에 | 에서; 를; 가
+			in front of the school | 학교 앞에 | 앞에 학교; 학교에 앞; 학교 앞을
+		`
+		}),
+		lesson({
+			id: 'ko-eating',
+			title: '밥을 먹어요',
+			summary: 'Present tense -아요/어요 and the object particle 을/를',
+			notes: `
+			### The polite present: -아요 / -어요
+			Take the dictionary form, remove **-다** to get the **stem**, then:
+			- last vowel **ㅏ or ㅗ** → add **-아요**: 받다 → 받**아요**, 좋다 → 좋**아요**
+			- any other vowel → add **-어요**: 먹다 → 먹**어요**, 읽다 → 읽**어요**
+			- **하다** → **해요**: 공부하다 → 공부**해요**
+
+			When the stem ends in a vowel, the vowels merge:
+			가다 → **가요**, 보다 → **봐요**, 마시다 → **마셔요**, 주다 → **줘요**, 배우다 → **배워요**.
+
+			### The object: 을 / 를
+			**을** after a consonant, **를** after a vowel: *밥**을** 먹어요*, *커피**를** 마셔요*.
+
+			### Asking for things
+			**Noun + 주세요** = "please give me": *물 주세요.*
+		`,
+			words: `
+			먹다 | to eat
+			마시다 | to drink
+			좋아하다 | to like
+			싫어하다 | to dislike
+			주다 | to give
+			밥 | rice; meal
+			고기 | meat
+			과일 | fruit
+			빵 | bread
+			라면 | ramyeon
+			물 | water
+			맥주 | beer
+			맛있다 | to be delicious
+			맛없다 | to taste bad
+			주세요 | please give me
+			많이 | a lot
+			같이 | together
+		`,
+			sentences: `
+			저는 밥을 먹어요. | I eat rice.
+			커피를 마셔요. | I drink coffee.
+			김치를 좋아해요? | Do you like kimchi?
+			이 라면 정말 맛있어요! | This ramyeon is really delicious!
+			물 주세요. | Water, please.
+			같이 먹어요. | Let's eat together.
+			저는 고기를 안 먹어요. | I don't eat meat.
+		`,
+			drills: `
+			먹다 → | 먹어요 | 먹아요; 먹요; 먹해요
+			가다 → | 가요 | 가아요; 가어요; 갸요
+			마시다 → | 마셔요 | 마시어요; 마사요; 마시요
+			공부하다 → | 공부해요 | 공부하요; 공부하아요; 공부어요
+			보다 → | 봐요 | 보요; 버요; 보어요
+			커피___ 마셔요. | 를 | 을; 가; 는
+			빵___ 먹어요. | 을 | 를; 이; 은
+		`
+		}),
+		lesson({
+			id: 'ko-going',
+			title: '어디에 가요?',
+			summary: 'Going places: 에, 에서 and (으)로',
+			notes: `
+			### 에 vs 에서
+			- **에** — destination or location of existence: *학교**에** 가요* (I go to school), *집**에** 있어요* (I'm at home).
+			- **에서** — the place where an **action** happens, or "from": *학교**에서** 공부해요* (I study at school), *서울**에서** 왔어요* (I came from Seoul).
+
+			### (으)로 — by, towards
+			- Means of transport: *버스**로** 가요*, *지하철**로** 와요*.
+			- Direction: *오른쪽**으로** 가세요* — go to the right.
+			**으로** after a consonant (except ㄹ), **로** after a vowel or ㄹ: *지하철**로***, *집**으로***.
+
+			**타다** = to ride/take (transport), with 을/를: *버스를 타요.*
+		`,
+			words: `
+			가다 | to go
+			오다 | to come
+			타다 | to ride; to take (transport)
+			학교 | school
+			회사 | company; work
+			식당 | restaurant
+			카페 | café
+			도서관 | library
+			병원 | hospital
+			은행 | bank
+			공원 | park
+			시장 | market
+			지하철 | subway
+			버스 | bus
+			택시 | taxi
+			오른쪽 | right side
+			왼쪽 | left side
+		`,
+			sentences: `
+			어디에 가요? | Where are you going?
+			학교에 가요. | I'm going to school.
+			도서관에서 공부해요. | I study at the library.
+			지하철로 회사에 가요. | I go to work by subway.
+			택시를 타요. | I take a taxi.
+			어디에서 왔어요? | Where did you come from?
+			오른쪽으로 가세요. | Go to the right.
+		`,
+			drills: `
+			I go to the park: 공원___ 가요. | 에 | 에서; 을; 로
+			I eat at a restaurant: 식당___ 먹어요. | 에서 | 에; 으로; 를 | An action happens there: 에서.
+			by bus: 버스___ | 로 | 으로; 에; 에서
+			by subway: 지하철___ | 로 | 으로; 에서; 을 | Ends in ㄹ: 로.
+			to the house: 집___ 가요 (towards) | 으로 | 로; 에서; 를
+			I take the bus: 버스___ 타요. | 를 | 에; 로; 가
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/a2.ts

@@ -0,0 +1,426 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a2',
+	'A2',
+	'Elementary',
+	'Past and future, negation, connecting sentences, abilities and honorifics.',
+	[
+		lesson({
+			id: 'ko-past',
+			title: '어제 뭐 했어요?',
+			summary: 'The past tense -았어요/었어요',
+			notes: `
+			The past tense is built on the same 아/어 form as the present. Replace **-요** with **-ㅆ어요**:
+
+			| dictionary | present | past |
+			|---|---|---|
+			| 가다 | 가요 | **갔어요** |
+			| 먹다 | 먹어요 | **먹었어요** |
+			| 보다 | 봐요 | **봤어요** |
+			| 마시다 | 마셔요 | **마셨어요** |
+			| 하다 | 해요 | **했어요** |
+			| 이다 | 이에요 | **이었어요 / 였어요** |
+
+			Time words usually come first: *어제 영화를 봤어요.*
+			Useful: **어제** (yesterday), **지난주** (last week), **작년** (last year), **주말에** (at the weekend), **아까** (a moment ago).
+		`,
+			words: `
+			어제 | yesterday
+			그저께 | the day before yesterday
+			지난주 | last week
+			작년 | last year
+			주말 | weekend
+			아까 | a little while ago
+			영화 | movie
+			보다 | to see; to watch
+			만나다 | to meet
+			친구 | friend
+			쇼핑하다 | to go shopping
+			운동하다 | to exercise
+			자다 | to sleep
+			일하다 | to work
+		`,
+			sentences: `
+			어제 뭐 했어요? | What did you do yesterday?
+			친구를 만났어요. | I met a friend.
+			주말에 영화를 봤어요. | I watched a movie at the weekend.
+			아침을 먹었어요? | Did you eat breakfast?
+			작년에 한국에 갔어요. | I went to Korea last year.
+			어제 늦게 잤어요. | I went to bed late yesterday.
+			그때 저는 학생이었어요. | Back then I was a student.
+		`,
+			drills: `
+			가다 → past | 갔어요 | 가었어요; 갔아요; 가았어요
+			먹다 → past | 먹었어요 | 먹았어요; 먹어요; 먹였어요
+			보다 → past | 봤어요 | 봐었어요; 봐어요; 봣어요
+			하다 → past | 했어요 | 하었어요; 핬어요; 햇어요
+			마시다 → past | 마셨어요 | 마시었요; 마샀어요; 마셔었어요
+			의사 + was | 의사였어요 | 의사이었요; 의사였요; 의사있었어요
+		`
+		}),
+		lesson({
+			id: 'ko-future',
+			title: '내일 뭐 할 거예요?',
+			summary: 'Future -(으)ㄹ 거예요 and wanting -고 싶어요',
+			notes: `
+			### Future / plans: -(으)ㄹ 거예요
+			- Stem ends in a vowel: **-ㄹ 거예요**: 가다 → **갈 거예요**, 하다 → **할 거예요**
+			- Stem ends in a consonant: **-을 거예요**: 먹다 → **먹을 거예요**
+			- Stem ends in ㄹ: just **거예요**: 살다 → **살 거예요**
+
+			It also expresses a guess: *내일 비가 **올 거예요**.* — It'll probably rain tomorrow.
+
+			### Wanting: -고 싶어요
+			Stem + **-고 싶어요** = I want to …: *한국에 가**고 싶어요**.*
+			For a third person, use **-고 싶어해요**: *동생이 가고 싶어해요.*
+
+			### Let's: -(으)ㅂ시다 / -아요
+			The polite present doubles as "let's": *같이 가요!* — Let's go together!
+		`,
+			words: `
+			내일 | tomorrow
+			모레 | the day after tomorrow
+			다음 주 | next week
+			내년 | next year
+			나중에 | later
+			여행 | trip; travel
+			여행하다 | to travel
+			계획 | plan
+			배우다 | to learn
+			살다 | to live
+			비 | rain
+			오다 | to come; (rain) to fall
+			휴가 | vacation; leave
+		`,
+			sentences: `
+			내일 뭐 할 거예요? | What will you do tomorrow?
+			친구하고 영화를 볼 거예요. | I'm going to watch a movie with a friend.
+			내년에 서울에서 살 거예요. | I'm going to live in Seoul next year.
+			한국어를 배우고 싶어요. | I want to learn Korean.
+			뭐 먹고 싶어요? | What do you want to eat?
+			내일 비가 올 거예요. | It will probably rain tomorrow.
+			휴가 때 제주도에 가고 싶어요. | I want to go to Jeju Island during my vacation.
+		`,
+			drills: `
+			가다 → future | 갈 거예요 | 가을 거예요; 가 거예요; 갈 거에요
+			먹다 → future | 먹을 거예요 | 먹ㄹ 거예요; 멀 거예요; 먹 거예요
+			만들다 → future | 만들 거예요 | 만들을 거예요; 만드를 거예요; 만들ㄹ 거예요 | Stems in ㄹ just add 거예요.
+			보다 → want to | 보고 싶어요 | 봐고 싶어요; 보 싶어요; 보고 싶아요
+			I want to rest: 쉬___ | 쉬고 싶어요 | 쉬어 싶어요; 쉬고 싶어해요; 쉴 싶어요
+		`
+		}),
+		lesson({
+			id: 'ko-negation',
+			title: '안 가요, 못 가요',
+			summary: 'Negation: 안, 못, -지 않다 and -지 못하다',
+			notes: `
+			### 안 — "don't" (choice or simple fact)
+			Put **안** before the verb: *안 가요* (I don't go), *안 비싸요* (it's not expensive).
+			For **noun + 하다** verbs, 안 goes before 하다: *공부 **안** 해요* (not ~~안 공부해요~~).
+
+			### 못 — "can't" (inability)
+			*못 가요* — I can't go. *수영 **못** 해요* — I can't swim.
+
+			### Long forms (more formal, written)
+			- stem + **-지 않아요** = 안: *가지 않아요*
+			- stem + **-지 못해요** = 못: *가지 못해요*
+
+			Some verbs have their own opposite instead: **있다 ↔ 없다**, **알다 ↔ 모르다**, **이다 ↔ 아니다**, 맛있다 ↔ 맛없다.
+		`,
+			words: `
+			안 | not
+			못 | cannot
+			알다 | to know
+			모르다 | to not know
+			수영하다 | to swim
+			운전하다 | to drive
+			노래하다 | to sing
+			매운 음식 | spicy food
+			바쁘다 | to be busy
+			피곤하다 | to be tired
+			아프다 | to be sick; to hurt
+			오늘 | today
+		`,
+			sentences: `
+			저는 고기를 안 먹어요. | I don't eat meat.
+			오늘은 안 바빠요. | I'm not busy today.
+			저는 수영 못 해요. | I can't swim.
+			몰라요. | I don't know.
+			아파서 학교에 못 갔어요. | I was sick so I couldn't go to school.
+			매운 음식을 먹지 않아요. | I don't eat spicy food.
+			오늘은 운동 안 했어요. | I didn't exercise today.
+		`,
+			drills: `
+			I don't study: | 공부 안 해요 | 안 공부해요; 공부 못 안 해요; 공부해 안요 | 안 goes between the noun and 하다.
+			I can't drive: | 운전 못 해요 | 못 운전해요; 운전 안 해요; 운전 못 하요
+			I don't know: | 몰라요 | 안 알아요; 몰아요; 모라요
+			There is no time: 시간이 ___ | 없어요 | 안 있어요; 못 있어요; 아니에요
+			가다 → long negative | 가지 않아요 | 가지 안아요; 안 가지요; 가지 않어요
+		`
+		}),
+		lesson({
+			id: 'ko-days',
+			title: '월요일부터 금요일까지',
+			summary: 'Days of the week, parts of the day, time particles',
+			notes: `
+			### Days of the week (요일)
+			| | | |
+			|---|---|---|
+			| 월요일 Monday (moon) | 화요일 Tuesday (fire) | 수요일 Wednesday (water) |
+			| 목요일 Thursday (wood) | 금요일 Friday (gold) | 토요일 Saturday (earth) |
+			| 일요일 Sunday (sun) | | |
+
+			### Time particles
+			- **에** — at/on a time: *월요일**에***, *세 시**에***. Not used with 어제, 오늘, 내일, 지금.
+			- **부터 … 까지** — from … until (time): *아홉 시**부터** 여섯 시**까지***.
+			- **에서 … 까지** — from … to (place): *서울**에서** 부산**까지***.
+
+			Parts of the day: **아침** (morning; also breakfast), **점심** (lunchtime; lunch), **저녁** (evening; dinner), **밤** (night), **오전** (a.m.), **오후** (p.m.).
+		`,
+			words: `
+			월요일 | Monday
+			화요일 | Tuesday
+			수요일 | Wednesday
+			목요일 | Thursday
+			금요일 | Friday
+			토요일 | Saturday
+			일요일 | Sunday
+			아침 | morning; breakfast
+			점심 | lunch; midday
+			저녁 | evening; dinner
+			밤 | night
+			오전 | a.m.; morning
+			오후 | p.m.; afternoon
+			매일 | every day
+			부터 | from (time)
+			까지 | until; to
+		`,
+			sentences: `
+			오늘은 무슨 요일이에요? | What day is it today?
+			월요일부터 금요일까지 일해요. | I work from Monday to Friday.
+			토요일에 뭐 해요? | What are you doing on Saturday?
+			아침에 커피를 마셔요. | I drink coffee in the morning.
+			저녁 먹었어요? | Did you have dinner?
+			서울에서 부산까지 세 시간 걸려요. | It takes three hours from Seoul to Busan.
+			오후 두 시에 만나요. | Let's meet at 2 p.m.
+		`,
+			drills: `
+			on Friday: 금요일___ | 에 | 에서; 부터; 을
+			tomorrow (no particle needed): ___ 가요 | 내일 | 내일에; 내일에서; 내일을 | 어제, 오늘, 내일 don't take 에.
+			from 9 until 5: 아홉 시___ 다섯 시까지 | 부터 | 에서; 에; 까지
+			from Seoul to Busan: 서울___ 부산까지 | 에서 | 부터; 에; 로
+			The day after 수요일 is: | 목요일 | 화요일; 금요일; 토요일
+		`
+		}),
+		lesson({
+			id: 'ko-shopping',
+			title: '이거 얼마예요?',
+			summary: 'Shopping, counters and polite requests',
+			notes: `
+			### Asking for things
+			- **Noun + 주세요**: *이거 주세요* — This one, please.
+			- **Verb + -아/어 주세요** — please do (for me): *깎아 주세요* — please give me a discount, *보여 주세요* — please show me.
+
+			### More counters
+			| counter | for |
+			|---|---|
+			| 개 | general things |
+			| 병 | bottles |
+			| 잔 | cups, glasses |
+			| 장 | flat things: paper, tickets, photos |
+			| 권 | books |
+			| 벌 | clothes (sets) |
+			| 켤레 | pairs of shoes/socks |
+
+			Paying: **카드** (card), **현금** (cash). *카드 돼요?* — Do you take cards?
+		`,
+			words: `
+			사다 | to buy
+			팔다 | to sell
+			비싸다 | to be expensive
+			싸다 | to be cheap
+			얼마예요 | how much is it
+			깎다 | to cut (price); to discount
+			카드 | card
+			현금 | cash
+			영수증 | receipt
+			병 | bottle (counter)
+			잔 | cup; glass (counter)
+			장 | sheet (counter)
+			신발 | shoes
+			사이즈 | size
+			다른 | other; different
+			봉투 | bag; envelope
+		`,
+			sentences: `
+			이거 얼마예요? | How much is this?
+			너무 비싸요. 좀 깎아 주세요. | It's too expensive. Please give me a discount.
+			물 두 병 주세요. | Two bottles of water, please.
+			카드 돼요? | Can I pay by card?
+			다른 사이즈 있어요? | Do you have another size?
+			영수증 주세요. | A receipt, please.
+			봉투 필요하세요? | Do you need a bag?
+			표 한 장 주세요. | One ticket, please.
+		`,
+			drills: `
+			two bottles of beer: 맥주 두 ___ | 병 | 잔; 장; 개
+			one ticket: 표 한 ___ | 장 | 병; 권; 명
+			three books: 책 세 ___ | 권 | 장; 개; 벌
+			Please show me: | 보여 주세요 | 보 주세요; 봐 주세요요; 보이 주세요
+			It's cheap: | 싸요 | 사요; 싸아요; 쌌요
+		`
+		}),
+		lesson({
+			id: 'ko-connecting',
+			title: '그리고, 그래서',
+			summary: 'Connecting sentences: -고, -아서/어서, 그런데',
+			notes: `
+			### Between sentences
+			| | |
+			|---|---|
+			| 그리고 | and (then) |
+			| 그래서 | so, therefore |
+			| 그런데 | but, by the way |
+			| 하지만 / 그렇지만 | but, however |
+			| 그러면 / 그럼 | then, in that case |
+
+			### Inside one sentence
+			- **-고** — and (listing, or sequence): *밥을 먹**고** 커피를 마셔요.*
+			- **-아서/어서** — because / and then (linked actions): *배가 고**파서** 밥을 먹었어요.* *학교에 가**서** 공부해요* (go to school and study there).
+
+			**-아서/어서** never takes the past tense itself; the final verb carries the tense: ~~갔어서~~ → *가서*.
+			It also can't be used with commands or suggestions ("because it's cold, let's …" uses **-(으)니까**, see B1).
+		`,
+			words: `
+			그리고 | and
+			그래서 | so
+			그런데 | but; by the way
+			하지만 | but; however
+			그럼 | then; in that case
+			배고프다 | to be hungry
+			배부르다 | to be full
+			늦다 | to be late
+			일찍 | early
+			늦게 | late
+			일어나다 | to get up
+			씻다 | to wash
+		`,
+			sentences: `
+			밥을 먹고 커피를 마셔요. | I eat and then drink coffee.
+			배고파서 라면을 먹었어요. | I was hungry so I ate ramyeon.
+			늦어서 미안해요. | Sorry I'm late.
+			아침에 일어나서 씻어요. | I get up in the morning and wash.
+			비가 와요. 그래서 집에 있어요. | It's raining. So I'm staying home.
+			맛있어요. 그런데 좀 비싸요. | It's tasty. But it's a bit expensive.
+			친구를 만나서 영화를 봤어요. | I met a friend and (we) watched a movie.
+		`,
+			drills: `
+			I was busy so I couldn't come: 바___ 못 왔어요. | 빠서 | 쁘서; 빴어서; 쁘고
+			늦다 + because: | 늦어서 | 늦아서; 늦었어서; 늦고서
+			It's cheap and tasty: 싸___ 맛있어요. | 고 | 서; 아서; 는데
+			I'm tired. ___ I'm going to sleep. | 그래서 | 그런데; 하지만; 그리고요
+		`
+		}),
+		lesson({
+			id: 'ko-can',
+			title: '수영할 수 있어요',
+			summary: 'Ability: -(으)ㄹ 수 있다 and -(으)ㄹ 줄 알다',
+			notes: `
+			### Can / can't: -(으)ㄹ 수 있어요 / 없어요
+			Vowel stem → **-ㄹ 수 있어요**, consonant → **-을 수 있어요**, ㄹ stem → **수 있어요**:
+			- *갈 수 있어요* — I can go
+			- *먹을 수 없어요* — I can't eat
+			- *만들 수 있어요* — I can make
+
+			### Know how to: -(으)ㄹ 줄 알아요 / 몰라요
+			For skills you've learned: *운전할 **줄 알아요*** — I know how to drive. *수영할 **줄 몰라요*** — I don't know how to swim.
+
+			Short form 못 (A2 negation) also expresses inability: *못 가요* ≈ *갈 수 없어요*.
+		`,
+			words: `
+			할 수 있다 | can do
+			할 수 없다 | cannot do
+			할 줄 알다 | to know how to do
+			피아노 | piano
+			치다 | to play (piano, tennis); to hit
+			기타 | guitar
+			한자 | Chinese characters
+			읽다 | to read
+			쓰다 | to write; to use
+			만들다 | to make
+			도와주다 | to help
+		`,
+			sentences: `
+			한국어를 읽을 수 있어요. | I can read Korean.
+			내일 올 수 있어요? | Can you come tomorrow?
+			오늘은 만날 수 없어요. | I can't meet today.
+			피아노를 칠 줄 알아요? | Do you know how to play the piano?
+			저는 운전할 줄 몰라요. | I don't know how to drive.
+			김치찌개를 만들 수 있어요. | I can make kimchi stew.
+			좀 도와줄 수 있어요? | Can you help me a bit?
+		`,
+			drills: `
+			읽다 → can | 읽을 수 있어요 | 읽 수 있어요; 읽ㄹ 수 있어요; 일 수 있어요
+			가다 → can | 갈 수 있어요 | 가을 수 있어요; 가 수 있어요; 갈 수 있다요
+			만들다 → can | 만들 수 있어요 | 만들을 수 있어요; 만들ㄹ 수 있어요; 만드는 수 있어요
+			I don't know how to swim: | 수영할 줄 몰라요 | 수영할 줄 안 알아요; 수영할 수 몰라요; 수영 줄 몰라요
+		`
+		}),
+		lesson({
+			id: 'ko-honorifics',
+			title: '할머니께서 주무세요',
+			summary: 'Honorifics: -(으)시-, special verbs and 께서',
+			notes: `
+			When talking **about** or **to** someone older or higher in status, Korean raises them with honorifics.
+
+			### -(으)세요 (honorific present)
+			stem + **-세요** (vowel) / **-으세요** (consonant): *가세요*, *읽으세요*. Past: **-(으)셨어요**: *가셨어요*.
+			This is also a polite command: *앉으세요* — please sit down.
+
+			### Special honorific verbs
+			| plain | honorific |
+			|---|---|
+			| 먹다 / 마시다 | 드시다 → 드세요 |
+			| 자다 | 주무시다 → 주무세요 |
+			| 있다 (be somewhere) | 계시다 → 계세요 |
+			| 말하다 | 말씀하시다 |
+			| 죽다 | 돌아가시다 |
+
+			### Honorific nouns and particles
+			이/가 → **께서**, 에게 → **께**. 이름 → **성함**, 나이 → **연세**, 집 → **댁**.
+			Never use honorifics for yourself: *저는 가요*, not ~~저는 가세요~~.
+		`,
+			words: `
+			할머니 | grandmother
+			할아버지 | grandfather
+			부모님 | parents
+			드시다 | to eat; to drink (honorific)
+			주무시다 | to sleep (honorific)
+			계시다 | to be (somewhere) (honorific)
+			말씀하시다 | to speak (honorific)
+			돌아가시다 | to pass away
+			성함 | name (honorific)
+			연세 | age (honorific)
+			댁 | home (honorific)
+			께서 | (honorific subject particle)
+		`,
+			sentences: `
+			할머니께서 주무세요. | Grandmother is sleeping.
+			많이 드세요. | Please eat a lot. (Enjoy your meal.)
+			성함이 어떻게 되세요? | May I ask your name?
+			할아버지께서 댁에 계세요. | Grandfather is at home.
+			연세가 어떻게 되세요? | May I ask how old you are?
+			여기 앉으세요. | Please sit here.
+			부모님께서 뭐 하세요? | What do your parents do?
+		`,
+			drills: `
+			Grandpa is eating: 할아버지께서 ___. | 드세요 | 먹으세요; 먹어요; 마세요
+			Mum is sleeping: 어머니께서 ___. | 주무세요 | 자세요; 자요; 주무어요
+			The teacher is in the office: 선생님께서 사무실에 ___. | 계세요 | 있으세요; 있어요; 게세요
+			Polite "sit down": | 앉으세요 | 앉세요; 앉아세요; 앉어세요
+			I'm going (about yourself): 저는 ___. | 가요 | 가세요; 가셔요; 가시어요 | Never use honorifics for yourself.
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/b1.ts

@@ -0,0 +1,404 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b1',
+	'B1',
+	'Intermediate',
+	'Obligation and permission, conditions, reasons, modifiers, experiences and the irregular verbs.',
+	[
+		lesson({
+			id: 'ko-must',
+			title: '해야 돼요',
+			summary: 'Must, may, and must not',
+			notes: `
+			| meaning | pattern | example |
+			|---|---|---|
+			| must, have to | -아/어야 해요 / 돼요 | 가**야 돼요** — I have to go |
+			| may, it's okay to | -아/어도 돼요 | 먹**어도 돼요?** — May I eat? |
+			| must not | -(으)면 안 돼요 | 찍**으면 안 돼요** — You mustn't take (photos) |
+			| don't have to | 안 -아/어도 돼요 | 안 가**도 돼요** — You don't have to go |
+
+			The 아/어 part follows the same rules as the present tense: 하다 → 해야, 가다 → 가야, 먹다 → 먹어야.
+			**해야 돼요** is more common in speech, **해야 해요** slightly more neutral.
+		`,
+			words: `
+			-아/어야 되다 | to have to
+			-아/어도 되다 | to be allowed to
+			-(으)면 안 되다 | to not be allowed to
+			사진 | photo
+			찍다 | to take (a photo)
+			담배 | cigarette
+			피우다 | to smoke
+			들어가다 | to go in
+			신발을 벗다 | to take off shoes
+			숙제 | homework
+			내다 | to submit; to pay
+			일찍 | early
+		`,
+			sentences: `
+			내일 일찍 일어나야 돼요. | I have to get up early tomorrow.
+			여기서 사진을 찍어도 돼요? | May I take photos here?
+			여기서 담배를 피우면 안 돼요. | You mustn't smoke here.
+			신발을 벗어야 해요. | You have to take off your shoes.
+			오늘 숙제를 내야 돼요. | I have to hand in my homework today.
+			안 와도 돼요. | You don't have to come.
+			들어가도 돼요? | May I come in?
+		`,
+			drills: `
+			가다 → must | 가야 돼요 | 가어야 돼요; 갈야 돼요; 가아야 돼요
+			먹다 → may | 먹어도 돼요 | 먹도 돼요; 먹아도 돼요; 먹으면 돼요
+			찍다 → must not | 찍으면 안 돼요 | 찍면 안 돼요; 찍어도 안 돼요; 안 찍으면 돼요
+			하다 → must | 해야 돼요 | 하야 돼요; 해도 돼요; 하어야 돼요
+			You don't have to pay: | 안 내도 돼요 | 내면 안 돼요; 안 내야 돼요; 내지 마도 돼요
+		`
+		}),
+		lesson({
+			id: 'ko-if-because',
+			title: '시간이 있으면',
+			summary: 'If -(으)면, because -(으)니까 and -기 때문에',
+			notes: `
+			### -(으)면 — if, when
+			*시간이 **있으면** 같이 가요.* — If you have time, let's go together.
+			Vowel/ㄹ stems: **-면** (가면, 살면); consonant stems: **-으면** (먹으면).
+
+			### Three ways to say "because"
+			| | use |
+			|---|---|
+			| -아/어서 | neutral cause; **not** with commands/suggestions |
+			| -(으)니까 | reason the speaker gives; **fine** with commands/suggestions |
+			| -기 때문에 | formal, emphasizes the cause |
+
+			- *추**우니까** 창문을 닫으세요.* — It's cold, so close the window. (command → 니까)
+			- ~~추워서 창문을 닫으세요~~ ✗
+			- Nouns: **(이)니까**, **때문에**: *비 **때문에*** — because of the rain.
+		`,
+			words: `
+			-(으)면 | if; when
+			-(으)니까 | because; since
+			-기 때문에 | because
+			때문에 | because of
+			시간 | time
+			날씨 | weather
+			춥다 | to be cold
+			덥다 | to be hot
+			창문 | window
+			닫다 | to close
+			열다 | to open
+			택시를 부르다 | to call a taxi
+		`,
+			sentences: `
+			시간이 있으면 같이 가요. | If you have time, let's go together.
+			한국에 가면 뭐 하고 싶어요? | What do you want to do if you go to Korea?
+			추우니까 창문을 닫으세요. | It's cold, so please close the window.
+			늦었으니까 택시를 탑시다. | It's late, so let's take a taxi.
+			비 때문에 못 갔어요. | I couldn't go because of the rain.
+			일이 많기 때문에 바빠요. | I'm busy because I have a lot of work.
+			모르면 물어보세요. | If you don't know, please ask.
+		`,
+			drills: `
+			먹다 → if | 먹으면 | 먹면; 먹어면; 먹으니까
+			살다 → if | 살면 | 살으면; 사면; 살아면
+			It's hot, so let's go inside: | 더우니까 들어갑시다 | 더워서 들어갑시다; 덥어서 들어갑시다; 덥으니까 들어갑시다 | Suggestions need -(으)니까.
+			because of the traffic: 교통___ | 때문에 | 이니까요; 기 때문에; 해서
+		`
+		}),
+		lesson({
+			id: 'ko-progressive',
+			title: '공부하고 있어요',
+			summary: 'Ongoing actions, intentions and purposes',
+			notes: `
+			### -고 있어요 — is doing (right now)
+			*지금 밥을 먹**고 있어요**.* — I'm eating right now. Honorific: **-고 계세요**.
+			Also for wearing: *안경을 쓰**고 있어요*** — he's wearing glasses.
+
+			### -(으)려고 해요 — intend to, plan to
+			*주말에 쉬**려고 해요**.* — I'm planning to rest at the weekend.
+			As a connector: *한국어를 배우**려고** 책을 샀어요.* — I bought a book (in order) to learn Korean.
+
+			### -(으)러 가다/오다 — go/come to (do)
+			Only with movement verbs: *밥 먹**으러** 가요* — I'm going to eat. *놀**러** 오세요!* — Come over (to hang out)!
+		`,
+			words: `
+			-고 있다 | to be …ing
+			-(으)려고 하다 | to intend to
+			-(으)러 가다 | to go to (do)
+			지금 | now
+			요즘 | these days
+			준비하다 | to prepare
+			찾다 | to look for; to find
+			놀다 | to play; to hang out
+			이사하다 | to move (house)
+			안경 | glasses
+			쓰다 | to wear (glasses, hat)
+		`,
+			sentences: `
+			지금 뭐 하고 있어요? | What are you doing now?
+			요즘 한국어를 배우고 있어요. | I'm learning Korean these days.
+			주말에 집에서 쉬려고 해요. | I'm planning to rest at home at the weekend.
+			다음 달에 이사하려고 해요. | I'm planning to move next month.
+			점심 먹으러 가요. | I'm going to have lunch.
+			우리 집에 놀러 오세요. | Come over to my place.
+			선물을 사려고 백화점에 갔어요. | I went to the department store to buy a present.
+		`,
+			drills: `
+			I'm reading now: 지금 읽___ | 고 있어요 | 어 있어요; 는 있어요; 고 계세요 | 계세요 is only for people you honour.
+			I intend to sleep: | 자려고 해요 | 잘려고 해요; 자으려고 해요; 자러 해요
+			I'm going to eat: 먹___ 가요. | 으러 | 러; 으려고 해; 고
+			I'm going to play: 놀___ 가요. | 러 | 으러; 을러; 고 | ㄹ stems take -러.
+		`
+		}),
+		lesson({
+			id: 'ko-modifiers',
+			title: '먹는 사람, 먹은 사람',
+			summary: 'Modifiers: turning verbs into adjectives for nouns',
+			notes: `
+			Korean puts the whole description **before** the noun. The verb's ending shows the time:
+
+			| | action verb | example |
+			|---|---|---|
+			| present | -는 | 먹**는** 사람 — the person who eats/is eating |
+			| past | -(으)ㄴ | 먹**은** 사람 — the person who ate |
+			| future | -(으)ㄹ | 먹**을** 사람 — the person who will eat |
+
+			**Descriptive verbs** (adjectives) use **-(으)ㄴ** for the present: *큰 집* (big house), *좋은 사람* (good person), *예쁜 꽃*.
+			**있다/없다** take **-는**: *맛있**는** 음식*, *재미없**는** 영화*.
+
+			ㄹ stems drop the ㄹ: 살다 → 사**는** 곳 (the place where I live), 멀다 → 먼 곳 (a far place).
+
+			Relative clauses: *어제 **본** 영화* — the film I watched yesterday. *내가 **좋아하는** 노래* — the song I like.
+		`,
+			words: `
+			큰 | big (modifier)
+			작은 | small (modifier)
+			좋은 | good (modifier)
+			예쁜 | pretty (modifier)
+			맛있는 | delicious (modifier)
+			재미있는 | fun (modifier)
+			사는 곳 | the place where (I) live
+			곳 | place
+			노래 | song
+			음식 | food
+			옷 | clothes
+			날 | day
+		`,
+			sentences: `
+			제가 좋아하는 음식은 비빔밥이에요. | The food I like is bibimbap.
+			어제 본 영화가 재미있었어요. | The movie I watched yesterday was fun.
+			내일 입을 옷이 없어요. | I have no clothes to wear tomorrow.
+			큰 가방을 샀어요. | I bought a big bag.
+			맛있는 식당을 알아요? | Do you know a good restaurant?
+			사는 곳이 어디예요? | Where do you live?
+			저기 서 있는 사람이 제 동생이에요. | The person standing over there is my younger sibling.
+		`,
+			drills: `
+			a big house: ___ 집 | 큰 | 크는; 클; 커
+			the book I'm reading: 제가 읽___ 책 | 는 | 은; 을; ㄴ
+			the book I read (past): 제가 읽___ 책 | 은 | 는; 을; 던은
+			a tasty restaurant: 맛있___ 식당 | 는 | 은; ㄴ; 을 | 있다/없다 take -는.
+			the place where I live: 제가 ___ 곳 | 사는 | 살는; 살은; 산는
+			the thing I will do: 제가 ___ 일 | 할 | 하는; 한; 하을
+		`
+		}),
+		lesson({
+			id: 'ko-contrast',
+			title: '비싸지만 좋아요',
+			summary: 'But and background: -지만, -는데',
+			notes: `
+			### -지만 — but (clear contrast)
+			*비싸**지만** 좋아요.* — It's expensive but good.
+			Works with any tense: *먹었**지만** 배고파요.*
+
+			### -는데 / -(으)ㄴ데 — softer "but", or giving background
+			- Action verbs and 있다/없다: **-는데** (가는데, 먹는데, 있는데)
+			- Descriptive verbs: **-(으)ㄴ데** (비싼데, 좋은데)
+			- Nouns: **-인데** (학생인데)
+			- Past: **-았/었는데** (갔는데)
+
+			Background: *배가 고픈**데** 밥 먹으러 갈까요?* — I'm hungry; shall we go eat?
+			Contrast: *한국어는 어려운**데** 재미있어요.* — Korean is hard, but fun.
+			At the end of a sentence, it softens or implies more: *좋은데요?* — It's (surprisingly) good!
+		`,
+			words: `
+			-지만 | but
+			-는데 | but; and (background)
+			어렵다 | to be difficult
+			쉽다 | to be easy
+			재미있다 | to be fun
+			조용하다 | to be quiet
+			시끄럽다 | to be noisy
+			비가 오다 | to rain
+			우산 | umbrella
+			같이 | together
+		`,
+			sentences: `
+			비싸지만 맛있어요. | It's expensive but tasty.
+			한국어는 어렵지만 재미있어요. | Korean is difficult but fun.
+			비가 오는데 우산이 없어요. | It's raining and I don't have an umbrella.
+			배고픈데 뭐 먹을까요? | I'm hungry; what shall we eat?
+			어제 전화했는데 안 받았어요. | I called yesterday but you didn't answer.
+			저는 학생인데 아르바이트도 해요. | I'm a student, but I also work part-time.
+		`,
+			drills: `
+			It's small but pretty: 작___ 예뻐요. | 지만 | 는데; 은지만; 아서
+			It's raining (background): 비가 오___ | 는데 | 은데; ㄴ데; 지만데
+			It's expensive (background): | 비싼데 | 비싸는데; 비쌌는데요; 비싸은데
+			I'm a student (background): 학생___ | 인데 | 는데; 은데; 이는데
+		`
+		}),
+		lesson({
+			id: 'ko-experience',
+			title: '먹어 본 적 있어요?',
+			summary: 'Trying and experience: -아/어 보다, -(으)ㄴ 적이 있다',
+			notes: `
+			### -아/어 보다 — try (doing)
+			*이거 먹**어 보세요**.* — Try eating this. *한번 입**어 볼게요**.* — I'll try it on.
+
+			### -(으)ㄴ 적이 있다/없다 — have (never) done
+			*한국에 가 **본 적이 있어요**?* — Have you ever been to Korea?
+			*아니요, 가 **본 적이 없어요**.* — No, I've never been.
+
+			Combining both (**-아/어 본 적이 있다**) is the most natural way to talk about experiences.
+
+			**-(으)ㄹ게요** — "I'll (do it)", a promise or decision made on the spot that affects the listener: *제가 **할게요**.* — I'll do it.
+		`,
+			words: `
+			-아/어 보다 | to try (doing)
+			-(으)ㄴ 적이 있다 | to have done before
+			한번 | once; (give it) a try
+			입다 | to wear; to put on (clothes)
+			신다 | to wear (shoes)
+			외국 | foreign country
+			번 | time(s) (counter)
+			처음 | first time
+			경험 | experience
+			-(으)ㄹ게요 | I will (promise)
+		`,
+			sentences: `
+			이거 한번 먹어 보세요. | Try this.
+			한국 음식을 먹어 본 적이 있어요? | Have you ever eaten Korean food?
+			저는 외국에 가 본 적이 없어요. | I've never been abroad.
+			이 옷을 입어 봐도 돼요? | May I try on these clothes?
+			제주도에 두 번 가 봤어요. | I've been to Jeju Island twice.
+			제가 전화할게요. | I'll call.
+			처음 먹어 봤어요. | It's the first time I've eaten it.
+		`,
+			drills: `
+			Try wearing it: 입___ 보세요. | 어 | 아; 고; 으러
+			Have you ever seen it? 본 ___ 있어요? | 적이 | 것이; 일이; 수가
+			I've never tried it: 해 본 적이 ___. | 없어요 | 안 있어요; 아니에요; 못 해요
+			I'll wait (promise): 기다릴___ | 게요 | 거예요; 까요; 래요
+		`
+		}),
+		lesson({
+			id: 'ko-irregulars',
+			title: 'Irregular verbs',
+			summary: 'ㅂ, ㄷ, 르, ㅅ and ㅎ irregulars',
+			notes: `
+			Some verbs change their stem before a vowel. Use the **Conjugation** drill to practise all of them.
+
+			| type | rule | example |
+			|---|---|---|
+			| ㅂ | ㅂ → 우 (돕다, 곱다: 오) | 춥다 → 추**워**요, 돕다 → 도**와**요 |
+			| ㄷ | ㄷ → ㄹ | 듣다 → 들**어**요, 걷다 → 걸어요 |
+			| 르 | 르 → ㄹ + 라/러 | 모르다 → 몰**라**요, 부르다 → 불**러**요 |
+			| ㅅ | ㅅ drops (no contraction) | 낫다 → 나**아**요, 짓다 → 지어요 |
+			| ㅎ | ㅎ drops, vowel → ㅐ | 그렇다 → 그**래**요, 빨갛다 → 빨개요 |
+			| 으 | ㅡ drops | 바쁘다 → 바**빠**요, 쓰다 → 써요 |
+			| ㄹ | ㄹ drops before ㄴ, ㅂ, ㅅ | 살다 → 사**세요**, 삽니다, 사는 |
+
+			Not every verb that looks irregular is: **입다** (입어요), **받다** (받아요), **웃다** (웃어요), **좋다** (좋아요) are regular.
+		`,
+			words: `
+			돕다 | to help
+			듣다 | to listen
+			걷다 | to walk
+			묻다 | to ask
+			모르다 | to not know
+			부르다 | to sing; to call
+			빠르다 | to be fast
+			다르다 | to be different
+			낫다 | to get better; to be better
+			짓다 | to build; to make up (a name)
+			그렇다 | to be so; to be like that
+			어떻다 | to be how
+			맵다 | to be spicy
+			무겁다 | to be heavy
+			가깝다 | to be close
+			귀엽다 | to be cute
+		`,
+			sentences: `
+			음악을 들어요. | I listen to music.
+			날씨가 추워요. | The weather is cold.
+			이 김치는 너무 매워요. | This kimchi is too spicy.
+			저도 잘 몰라요. | I don't really know either.
+			노래를 불러 주세요. | Please sing a song.
+			감기가 다 나았어요. | My cold is completely better.
+			어때요? 괜찮아요? | How is it? Is it okay?
+			집이 학교에서 가까워요. | My house is close to school.
+		`,
+			drills: `
+			듣다 → | 들어요 | 듣어요; 들아요; 드어요
+			맵다 → | 매워요 | 맵어요; 매와요; 매어요
+			모르다 → | 몰라요 | 모르어요; 모라요; 몰러요
+			낫다 → | 나아요 | 낫아요; 나요; 나사요 | ㅅ drops but the vowels don't merge.
+			그렇다 → | 그래요 | 그렇어요; 그러요; 그레요
+			입다 → | 입어요 | 이워요; 입아요; 이어요 | 입다 is regular.
+			살다 → honorific | 사세요 | 살으세요; 살세요; 사으세요
+		`
+		}),
+		lesson({
+			id: 'ko-feelings',
+			title: '기분이 어때요?',
+			summary: 'Feelings, and -아/어하다 for other people',
+			notes: `
+			Korean distinguishes **your own** feelings from **someone else's**.
+
+			For yourself, use the descriptive verb: *(저는) 슬퍼요* — I'm sad.
+			For others, add **-아/어하다** (to show signs of): *동생이 슬**퍼해요*** — my sibling is sad.
+
+			| I feel | someone else | meaning |
+			|---|---|---|
+			| 좋다 | 좋아하다 | like |
+			| 싫다 | 싫어하다 | dislike |
+			| 무섭다 | 무서워하다 | be scared |
+			| 부럽다 | 부러워하다 | be envious |
+			| 슬프다 | 슬퍼하다 | be sad |
+			| 기쁘다 | 기뻐하다 | be glad |
+
+			**기분** = mood: *기분이 좋아요* (I'm in a good mood). **화가 나다** = to get angry: *화가 났어요*.
+		`,
+			words: `
+			기분 | mood; feeling
+			행복하다 | to be happy
+			슬프다 | to be sad
+			기쁘다 | to be glad
+			화가 나다 | to get angry
+			걱정하다 | to worry
+			무섭다 | to be scary; to be scared
+			외롭다 | to be lonely
+			심심하다 | to be bored
+			신나다 | to be excited
+			부끄럽다 | to be embarrassed; to be shy
+			속상하다 | to be upset
+			설레다 | to be excited (fluttering)
+			스트레스를 받다 | to be stressed
+		`,
+			sentences: `
+			오늘 기분이 어때요? | How are you feeling today?
+			기분이 좋아요. | I'm in a good mood.
+			왜 화가 났어요? | Why are you angry?
+			걱정하지 마세요. | Don't worry.
+			주말에 너무 심심했어요. | I was so bored at the weekend.
+			동생이 개를 무서워해요. | My younger sibling is scared of dogs.
+			요즘 스트레스를 많이 받아요. | I'm very stressed these days.
+			내일 여행 가서 너무 설레요. | I'm so excited because I'm going on a trip tomorrow.
+		`,
+			drills: `
+			My friend is sad: 친구가 ___. | 슬퍼해요 | 슬퍼요; 슬프해요; 슬퍼하요 | For others, use -아/어하다.
+			I'm scared: (저는) ___. | 무서워요 | 무서워해요; 무섭어요; 무서와요
+			Don't worry: 걱정___ | 하지 마세요 | 안 하세요; 하지 않아요; 마세요 하지
+			He got angry: 화가 ___. | 났어요 | 했어요; 나요; 있었어요
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/b2.ts

@@ -0,0 +1,355 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b2',
+	'B2',
+	'Upper intermediate',
+	'Reported speech, casual speech, nuanced reasons, news vocabulary and idioms.',
+	[
+		lesson({
+			id: 'ko-reported',
+			title: '간다고 했어요',
+			summary: 'Reported speech: -다고, -냐고, -라고, -자고',
+			notes: `
+			Reported speech changes the ending by sentence type, then adds **하다** (or 말하다, 듣다…):
+
+			| type | action verb | descriptive verb | noun |
+			|---|---|---|---|
+			| statement | -(느)ㄴ다고 | -다고 | -(이)라고 |
+			| question | -냐고 | -냐고 | -(이)냐고 |
+			| command | -(으)라고 | — | — |
+			| suggestion | -자고 | — | — |
+
+			- *민수가 내일 **간다고** 했어요.* — Minsu said he's going tomorrow. (가다 → 간다)
+			- *날씨가 **좋다고** 해요.* — They say the weather is nice.
+			- *어디 **가냐고** 물어봤어요.* — (He) asked where I was going.
+			- *빨리 **오라고** 했어요.* — (She) told me to come quickly.
+			- *같이 **먹자고** 했어요.* — (He) suggested eating together.
+
+			Past: **-았/었다고**: *갔다고 했어요*. Contracted in speech: *간대요* (= 간다고 해요), *좋대요*, *오래요*.
+			"Give me" commands use **달라고**: *물을 **달라고** 했어요* — (He) asked for water.
+		`,
+			words: `
+			-다고 하다 | to say that
+			-냐고 하다 | to ask whether
+			-라고 하다 | to tell (someone) to
+			-자고 하다 | to suggest that
+			-대요 | they say (contracted)
+			물어보다 | to ask
+			전하다 | to pass on (a message)
+			소문 | rumour
+			뉴스 | news
+			결혼하다 | to get married
+			그만두다 | to quit
+		`,
+			sentences: `
+			민수 씨가 내일 온다고 했어요. | Minsu said he's coming tomorrow.
+			내일 비가 온대요. | They say it's going to rain tomorrow.
+			선생님이 숙제를 하라고 하셨어요. | The teacher told us to do our homework.
+			친구가 같이 영화 보자고 했어요. | My friend suggested watching a movie together.
+			어디에 사냐고 물어봤어요. | They asked where I live.
+			그 사람이 회사를 그만뒀다고 들었어요. | I heard that person quit the company.
+			두 사람이 결혼한대요! | They say the two of them are getting married!
+		`,
+			drills: `
+			He said he eats: 먹___ 했어요. | 는다고 | 다고; 냐고; 자고
+			She said it's cold: 춥___ 했어요. | 다고 | 는다고; ㄴ다고; 라고
+			He told me to go: 가___ 했어요. | 라고 | 자고; 다고; 냐고
+			She suggested going: 가___ 했어요. | 자고 | 라고; 냐고; 는다고
+			They asked if I'm a student: 학생이___ 물어봤어요. | 냐고 | 라고; 다고; 자고
+			They say it's delicious: 맛있___. | 대요 | 다요; 래요; 재요
+		`
+		}),
+		lesson({
+			id: 'ko-become-decide',
+			title: '하게 됐어요',
+			summary: '-게 되다, -기로 하다, -도록 and -게',
+			notes: `
+			### -게 되다 — end up, come to (not by one's own choice)
+			*회사 때문에 서울에서 살**게 됐어요**.* — I ended up living in Seoul because of work.
+			*김치를 좋아하**게 됐어요**.* — I've come to like kimchi.
+
+			### -기로 하다 — decide to
+			*담배를 끊**기로 했어요**.* — I decided to quit smoking.
+			Also for agreements: *내일 만나**기로 했어요**.* — We agreed to meet tomorrow.
+
+			### -도록 / -게 — so that, to the point that
+			*늦지 않**도록** 일찍 나가세요.* — Leave early so you're not late.
+			*잘 들리**게** 크게 말해 주세요.* — Please speak loudly so I can hear.
+			*밤새**도록*** — until the night is through.
+		`,
+			words: `
+			-게 되다 | to end up; to come to
+			-기로 하다 | to decide to
+			-도록 | so that
+			끊다 | to quit; to cut off
+			결정하다 | to decide
+			약속하다 | to promise
+			취직하다 | to get a job
+			유학하다 | to study abroad
+			외우다 | to memorize
+			들리다 | to be heard
+			밤새 | all night
+		`,
+			sentences: `
+			회사 때문에 부산에 살게 됐어요. | I ended up living in Busan because of work.
+			한국 드라마를 보고 한국어를 좋아하게 됐어요. | I came to love Korean after watching Korean dramas.
+			올해부터 운동하기로 했어요. | I decided to start exercising this year.
+			토요일에 만나기로 했어요. | We agreed to meet on Saturday.
+			잊어버리지 않도록 메모하세요. | Write it down so you don't forget.
+			다 들리게 크게 말해 주세요. | Please speak loudly so everyone can hear.
+		`,
+			drills: `
+			I decided to go: 가___ 했어요. | 기로 | 게; 도록; 려고
+			I ended up going: 가게 ___. | 됐어요 | 했어요; 있어요; 봤어요
+			so that you don't catch a cold: 감기에 걸리지 않___ | 도록 | 기로; 게 되; 려고
+			We agreed to meet: 만나기로 ___. | 했어요 | 됐어요; 봤어요; 있어요
+		`
+		}),
+		lesson({
+			id: 'ko-banmal',
+			title: '반말',
+			summary: 'Casual speech with friends',
+			notes: `
+			**반말** (casual speech) is used with close friends, younger people and family. Using it with strangers or elders is rude, so ask first: ***말 놓을까요?*** / ***반말해도 돼요?***
+
+			The basic rule: **drop the -요**.
+
+			| polite | casual |
+			|---|---|
+			| 가요 | **가** |
+			| 먹었어요 | **먹었어** |
+			| 할 거예요 | **할 거야** |
+			| 학생이에요 / 의사예요 | 학생**이야** / 의사**야** |
+			| 네 / 아니요 | **응 / 아니** |
+			| 저 / 제 | **나 / 내** |
+			| (you) | **너 / 네** (often said 니) |
+
+			Commands: *빨리 **와**!* Suggestions (let's): **-자**: *같이 **가자**!*
+			Names: *민수**야**!* (after a vowel), *지민**아**!* (after a consonant).
+		`,
+			words: `
+			반말 | casual speech
+			존댓말 | polite speech
+			응 | yeah
+			아니 | no; nah
+			나 | I (casual)
+			내 | my (casual)
+			너 | you (casual)
+			네 | your (casual)
+			뭐 해? | what are you doing?
+			밥 먹었어? | have you eaten?
+			진짜? | really?
+			괜찮아 | it's fine
+			가자 | let's go
+			말을 놓다 | to switch to casual speech
+		`,
+			sentences: `
+			뭐 해? | What are you doing?
+			밥 먹었어? | Have you eaten?
+			응, 먹었어. | Yeah, I ate.
+			내일 뭐 할 거야? | What are you doing tomorrow?
+			같이 영화 보자! | Let's watch a movie together!
+			나는 학생이야. | I'm a student.
+			우리 말 놓을까요? | Shall we speak casually?
+			지민아, 빨리 와! | Jimin, come quickly!
+		`,
+			drills: `
+			가요 → casual | 가 | 가자요; 가야; 간다요
+			먹었어요 → casual | 먹었어 | 먹었; 먹어써; 먹었야
+			의사예요 → casual | 의사야 | 의사이야; 의사예; 의사다요
+			학생이에요 → casual | 학생이야 | 학생야; 학생이에; 학생예
+			Let's eat! (casual) | 먹자 | 먹어자; 먹읍시다; 먹자요
+			Calling 민수: | 민수야 | 민수아; 민수씨야; 민수이야
+			Calling 지민: | 지민아 | 지민야; 지민이야아; 지민씨아
+		`
+		}),
+		lesson({
+			id: 'ko-cause',
+			title: '덕분에, 때문에',
+			summary: 'Good and bad reasons: 덕분에, 탓에, -는 바람에, -느라고',
+			notes: `
+			| pattern | nuance | example |
+			|---|---|---|
+			| -(으)ㄴ/는 덕분에 | thanks to (good result) | 도와준 **덕분에** 끝냈어요 |
+			| -(으)ㄴ/는 탓에 | because of (blame) | 늦게 일어난 **탓에** 지각했어요 |
+			| -는 바람에 | because of (unexpected, bad) | 차가 막히**는 바람에** 늦었어요 |
+			| -느라고 | because I was busy doing | 공부하**느라고** 못 잤어요 |
+
+			Nouns: *선생님 **덕분에***, *비 **탓에***.
+			**-느라고** needs the same subject in both clauses and an action verb, and the result is usually negative.
+			**-는 바람에** always takes the **-는** form, even for past events, and the main clause is past tense.
+		`,
+			words: `
+			덕분에 | thanks to
+			탓에 | because of (blame)
+			-는 바람에 | because (unexpectedly)
+			-느라고 | because (busy) doing
+			차가 막히다 | traffic is jammed
+			지각하다 | to be late (for school/work)
+			놓치다 | to miss (a bus, a chance)
+			끝내다 | to finish
+			잃어버리다 | to lose
+			고장 나다 | to break down
+		`,
+			sentences: `
+			도와준 덕분에 일을 빨리 끝냈어요. | Thanks to your help I finished the work quickly.
+			차가 막히는 바람에 늦었어요. | I was late because the traffic was jammed.
+			게임하느라고 숙제를 못 했어요. | I couldn't do my homework because I was busy gaming.
+			늦잠을 잔 탓에 버스를 놓쳤어요. | I missed the bus because I overslept.
+			휴대폰이 고장 나는 바람에 연락을 못 했어요. | My phone broke, so I couldn't contact you.
+			선생님 덕분에 시험에 합격했어요. | Thanks to my teacher, I passed the exam.
+		`,
+			drills: `
+			Thanks to the teacher: 선생님 ___ | 덕분에 | 탓에; 바람에; 느라고
+			I was busy studying and couldn't eat: 공부하___ 못 먹었어요. | 느라고 | 는 바람에; 덕분에; 기로
+			The bus suddenly broke down so I was late: 버스가 고장 나___ 늦었어요. | 는 바람에 | 느라고; 덕분에; 기 위해
+		`
+		}),
+		lesson({
+			id: 'ko-retrospective',
+			title: '가던 길, 먹었던 음식',
+			summary: 'Recollection: -던, -았/었던, -더라고요',
+			notes: `
+			### -던 — an ongoing or repeated action in the past, often unfinished
+			*제가 마시**던** 커피 어디 있어요?* — Where's the coffee I was drinking?
+			*자주 가**던** 카페* — the café I used to go to.
+
+			### -았/었던 — a completed past experience you're recalling
+			*작년에 먹**었던** 음식* — the food I ate last year (and remember).
+
+			### -더라고요 — reporting something you witnessed
+			*그 영화 정말 재미있**더라고요**.* — That movie was really fun (I saw it, I found).
+			Used for first-hand discoveries, not for your own actions.
+		`,
+			words: `
+			-던 | that was (…ing)
+			-았/었던 | that (I) did before
+			-더라고요 | I noticed that
+			자주 | often
+			예전에 | in the past
+			어릴 때 | in childhood
+			추억 | memory
+			그립다 | to miss (long for)
+			동네 | neighbourhood
+			옛날 | old days
+		`,
+			sentences: `
+			제가 마시던 커피 어디 있어요? | Where's the coffee I was drinking?
+			어릴 때 살던 동네에 가 봤어요. | I visited the neighbourhood I used to live in as a child.
+			작년에 갔던 식당에 또 갔어요. | I went again to the restaurant we went to last year.
+			그 식당 음식이 정말 맛있더라고요. | The food at that restaurant was really good (I found).
+			예전에 자주 듣던 노래예요. | It's a song I used to listen to often.
+			한국 사람들이 정말 친절하더라고요. | Korean people were really kind (from what I saw).
+		`,
+			drills: `
+			the book I was reading (unfinished): 읽___ 책 | 던 | 었던; 는; 을
+			the place we visited last year: 작년에 갔___ 곳 | 던 | 는; 을; 더라
+			It was really cold (I found): 정말 춥___ | 더라고요 | 던요; 었던요; 었다고요
+		`
+		}),
+		lesson({
+			id: 'ko-news',
+			title: '뉴스와 사회',
+			summary: 'Society, politics and news vocabulary',
+			notes: `
+			News Korean is heavy in **Sino-Korean** words and uses the written **-다** style (see C1).
+
+			Headlines drop particles and end in nouns: *"대통령, 오늘 기자회견 **발표**"* — President to hold press conference today.
+
+			Common verb pattern: **noun + 하다 / 되다** (active / passive):
+			*발표하다* (to announce) / *발표되다* (to be announced), *증가하다* (to increase), *감소하다* (to decrease).
+		`,
+			words: `
+			정부 | government
+			대통령 | president
+			국회 | National Assembly
+			선거 | election
+			투표하다 | to vote
+			정당 | political party
+			경제 | economy
+			사회 | society
+			기자 | reporter
+			사건 | incident; case
+			사고 | accident
+			환경 | environment
+			발표하다 | to announce
+			증가하다 | to increase
+			감소하다 | to decrease
+			물가 | prices; cost of living
+			인구 | population
+			저출산 | low birth rate
+		`,
+			sentences: `
+			다음 달에 선거가 있어요. | There's an election next month.
+			정부가 새로운 정책을 발표했어요. | The government announced a new policy.
+			요즘 물가가 너무 올랐어요. | Prices have gone up so much lately.
+			한국의 인구가 감소하고 있어요. | Korea's population is decreasing.
+			저출산은 큰 사회 문제예요. | The low birth rate is a big social problem.
+			어제 큰 교통사고가 났어요. | There was a big traffic accident yesterday.
+			환경을 보호해야 해요. | We have to protect the environment.
+		`,
+			drills: `
+			to announce | 발표하다 | 발전하다; 발견하다; 방문하다
+			prices / cost of living | 물가 | 가격표; 물건; 값어치
+			The population is decreasing: 인구가 ___ 있어요. | 감소하고 | 증가하고; 감소되고; 줄이고
+			There was an accident: 사고가 ___. | 났어요 | 했어요; 됐어요; 있었다요
+		`
+		}),
+		lesson({
+			id: 'ko-idioms',
+			title: '관용어와 속담',
+			summary: 'Idioms and proverbs',
+			notes: `
+			### Body idioms (관용어)
+			| idiom | literally | meaning |
+			|---|---|---|
+			| 발이 넓다 | feet are wide | to know a lot of people |
+			| 눈이 높다 | eyes are high | to have high standards |
+			| 손이 크다 | hands are big | to be generous (makes/gives a lot) |
+			| 입이 짧다 | mouth is short | to be a picky eater |
+			| 귀가 얇다 | ears are thin | to be easily persuaded |
+			| 배가 아프다 | stomach hurts | to be jealous (of someone's success) |
+			| 미역국을 먹다 | to eat seaweed soup | to fail an exam |
+
+			### Proverbs (속담)
+			- **누워서 떡 먹기** — eating rice cake lying down: a piece of cake.
+			- **식은 죽 먹기** — eating cold porridge: very easy.
+			- **고생 끝에 낙이 온다** — after hardship comes joy.
+			- **가는 말이 고와야 오는 말이 곱다** — kind words out bring kind words back.
+			- **원숭이도 나무에서 떨어진다** — even monkeys fall from trees.
+			- **낮말은 새가 듣고 밤말은 쥐가 듣는다** — birds hear daytime words, mice hear night words (walls have ears).
+			- **백문이 불여일견** — hearing a hundred times isn't as good as seeing once.
+		`,
+			words: `
+			발이 넓다 | to know a lot of people
+			눈이 높다 | to have high standards
+			손이 크다 | to be generous
+			입이 짧다 | to be a picky eater
+			귀가 얇다 | to be gullible
+			배가 아프다 | to be jealous
+			미역국을 먹다 | to fail an exam
+			누워서 떡 먹기 | a piece of cake
+			식은 죽 먹기 | very easy
+			고생 끝에 낙이 온다 | after hardship comes happiness
+			원숭이도 나무에서 떨어진다 | even experts make mistakes
+			백문이 불여일견 | seeing is believing
+		`,
+			sentences: `
+			그 시험은 누워서 떡 먹기였어요. | That exam was a piece of cake.
+			민수는 발이 넓어서 친구가 많아요. | Minsu knows a lot of people, so he has many friends.
+			제 동생은 눈이 너무 높아요. | My younger sibling has very high standards.
+			우리 어머니는 손이 커요. | My mother is very generous (always makes a lot of food).
+			시험에서 미역국을 먹었어요. | I failed the exam.
+			원숭이도 나무에서 떨어진다고 하잖아요. | They do say even monkeys fall from trees.
+		`,
+			drills: `
+			to know a lot of people: 발이 ___ | 넓다 | 크다; 길다; 많다
+			very easy: 식은 ___ 먹기 | 죽 | 밥; 떡; 국
+			to fail an exam: ___을 먹다 | 미역국 | 떡국; 김치; 죽
+			to have high standards: 눈이 ___ | 높다 | 크다; 넓다; 밝다
+			even monkeys fall from ___ | 나무에서 | 산에서; 하늘에서; 집에서
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/c1.ts

@@ -0,0 +1,297 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'c1',
+	'C1',
+	'Advanced',
+	'Written style, advanced connectors, Sino-Korean roots, sentence-final nuance and four-character idioms.',
+	[
+		lesson({
+			id: 'ko-written',
+			title: '한다체',
+			summary: 'The written plain style used in books, news and essays',
+			notes: `
+			Newspapers, books, essays and diaries use the plain **한다체**:
+
+			| | action verb | descriptive verb | noun |
+			|---|---|---|---|
+			| present | -(느)ㄴ다: 간다, 먹는다 | -다: 크다, 좋다 | -(이)다: 학생이다 |
+			| past | -았/었다: 갔다 | -았/었다: 컸다 | -였다/이었다 |
+			| future | -(으)ㄹ 것이다 | -(으)ㄹ 것이다 | |
+			| question | -는가? / -나? | -(으)ㄴ가? | |
+
+			Written connectors: **-(으)며** (and, while), **-고자** (in order to), **및** (and), **등** (etc.), **따라서** (therefore), **그러므로** (hence), **한편** (meanwhile), **즉** (that is).
+		`,
+			words: `
+			-(으)며 | and; while (written)
+			-고자 | in order to (formal)
+			및 | and (written)
+			등 | etc.; and so on
+			따라서 | therefore
+			그러므로 | hence
+			한편 | meanwhile
+			즉 | that is; namely
+			예를 들어 | for example
+			결론적으로 | in conclusion
+			연구 | research
+			결과 | result
+			나타나다 | to appear; to be shown
+		`,
+			sentences: `
+			나는 매일 아침 커피를 마신다. | I drink coffee every morning.
+			한국의 인구는 점점 줄어들고 있다. | Korea's population is gradually decreasing.
+			이 문제를 해결하고자 한다. | (We) intend to solve this problem.
+			연구 결과는 다음과 같다. | The results of the study are as follows.
+			따라서 새로운 방법이 필요하다. | Therefore, a new method is needed.
+			그는 가수이며 배우이다. | He is a singer and an actor.
+		`,
+			drills: `
+			가다 → 한다체 present | 간다 | 가다; 가는다; 갑니다
+			먹다 → 한다체 present | 먹는다 | 먹다; 먹ㄴ다; 먹은다
+			좋다 → 한다체 present | 좋다 | 좋는다; 좋ㄴ다; 좋은다 | Descriptive verbs keep -다.
+			학생이에요 → 한다체 | 학생이다 | 학생다; 학생이는다; 학생인다
+			in order to solve: 해결하___ | 고자 | 며; 는가; 고서
+		`
+		}),
+		lesson({
+			id: 'ko-connectors',
+			title: '뿐만 아니라',
+			summary: 'Advanced connectors',
+			notes: `
+			| pattern | meaning | example |
+			|---|---|---|
+			| -(으)ㄹ 뿐만 아니라 | not only … but also | **쌀 뿐만 아니라** 맛있어요 |
+			| -(으)ㄴ/는 반면에 | whereas, on the other hand | 형은 키가 큰 **반면에** 동생은 작아요 |
+			| -(으)ㄴ/는 데다가 | on top of that | 비가 오**는 데다가** 바람도 불어요 |
+			| -(으)ㄴ/는 대신에 | instead of; in exchange for | 영화를 보**는 대신에** 책을 읽었어요 |
+			| -(으)ㄹ수록 | the more … the more | 보**면 볼수록** 좋아요 |
+			| -(으)ㄴ/는 김에 | while (one is at it) | 나가**는 김에** 우유 좀 사 와 |
+			| -다 보면 | if you keep doing | 계속 연습하**다 보면** 늘 거예요 |
+			| -(으)ㄹ 텐데 | it would/must … (supposition) | 피곤**할 텐데** 쉬세요 |
+		`,
+			words: `
+			뿐만 아니라 | not only … but also
+			반면에 | on the other hand
+			-는 데다가 | on top of
+			대신에 | instead of
+			-(으)ㄹ수록 | the more … the more
+			-는 김에 | while at it
+			-다 보면 | if you keep …ing
+			-(으)ㄹ 텐데 | it must be … (so)
+			늘다 | to improve; to increase
+			바람이 불다 | the wind blows
+		`,
+			sentences: `
+			이 식당은 쌀 뿐만 아니라 맛도 있어요. | This restaurant is not only cheap but also tasty.
+			서울은 복잡한 반면에 편리해요. | Seoul is hectic but on the other hand convenient.
+			비가 오는 데다가 바람도 많이 불어요. | It's raining and on top of that it's very windy.
+			한국어는 배우면 배울수록 재미있어요. | The more you learn Korean, the more fun it is.
+			나가는 김에 쓰레기 좀 버려 줘. | Since you're going out, take the trash out.
+			계속 연습하다 보면 늘 거예요. | If you keep practising, you'll improve.
+			피곤할 텐데 좀 쉬세요. | You must be tired, so rest a bit.
+		`,
+			drills: `
+			the more I see, the more I like: 보면 ___ 좋아요 | 볼수록 | 보는 김에; 볼 뿐; 보다 보면
+			not only fast but also cheap: 빠를 ___ 싸요 | 뿐만 아니라 | 반면에; 대신에; 텐데
+			Instead of rice, I ate bread: 밥 ___ 빵을 먹었어요 | 대신에 | 반면에; 김에; 뿐만
+			You must be hungry (so eat): 배고플 ___ 드세요 | 텐데 | 수록; 김에; 뿐
+		`
+		}),
+		lesson({
+			id: 'ko-hanja',
+			title: '한자어',
+			summary: 'Sino-Korean roots that unlock hundreds of words',
+			notes: `
+			About 60% of Korean vocabulary comes from Chinese characters (**한자**). Learning common roots lets you guess new words.
+
+			| root | meaning | words |
+			|---|---|---|
+			| 학 (學) | study | 학생, 학교, 대학, 과학, 학자 |
+			| 생 (生) | life, birth | 학생, 생일, 인생, 생활, 선생 |
+			| 인 (人) | person | 한국인, 외국인, 인구, 인간 |
+			| 대 (大) | big | 대학, 대통령, 대사관, 대회 |
+			| 국 (國) | country | 한국, 외국, 국가, 국제 |
+			| 식 (食) | eat | 식당, 음식, 식사, 한식 |
+			| 전 (電) | electricity | 전화, 전기, 전철, 전자 |
+			| 동 (東) / 서 (西) / 남 (南) / 북 (北) | east / west / south / north | 동양, 서양, 남한, 북한 |
+			| 시 (市) | city, market | 시장, 시민, 도시 |
+			| 문 (文) | writing | 문화, 문학, 문자, 논문 |
+
+			*외국인* = 외 (outside) + 국 (country) + 인 (person) = foreigner.
+		`,
+			words: `
+			한자 | Chinese characters
+			과학 | science
+			인생 | life
+			생활 | daily life
+			외국인 | foreigner
+			인간 | human
+			대사관 | embassy
+			국제 | international
+			식사 | meal
+			한식 | Korean food
+			전기 | electricity
+			전자 | electronic
+			동양 | the East; Asia
+			서양 | the West
+			시민 | citizen
+			도시 | city
+			문화 | culture
+			문학 | literature
+		`,
+			sentences: `
+			한국어 단어의 많은 부분이 한자어예요. | A large part of Korean vocabulary is Sino-Korean.
+			외국인 등록증을 받았어요. | I received my foreigner registration card.
+			대사관에 가야 해요. | I have to go to the embassy.
+			동양 문화와 서양 문화는 많이 달라요. | Eastern and Western cultures are very different.
+			식사하셨어요? | Have you eaten? (polite greeting)
+			이 도시는 인구가 많아요. | This city has a large population.
+		`,
+			drills: `
+			외국인 means: | foreigner | foreign country; international; embassy
+			The root 식 (食) means: | eat | study; city; life
+			The root 학 (學) means: | study | person; big; country
+			Which word contains "person" (人)? | 인구 | 학교; 식당; 전화
+			국제 means: | international | domestic; national anthem; foreigner
+		`
+		}),
+		lesson({
+			id: 'ko-endings',
+			title: '잖아요, 거든요, 네요',
+			summary: 'Sentence endings that add nuance',
+			notes: `
+			These endings don't change the facts, only the speaker's attitude.
+
+			| ending | nuance | example |
+			|---|---|---|
+			| -잖아요 | "you know", reminding of shared knowledge | 내일 시험이**잖아요**. — There's a test tomorrow, you know. |
+			| -거든요 | giving a reason or background the listener doesn't know | 오늘 바쁘**거든요**. — (Because) I'm busy today, you see. |
+			| -네요 | spontaneous reaction to what you just noticed | 예쁘**네요**! — Oh, it's pretty! |
+			| -군요 / -구나 | realization (a bit more formal / casual) | 그랬**군요**. — I see, so that's what happened. |
+			| -지요 / -죠 | seeking agreement, "right?" | 맛있**죠**? — It's tasty, right? |
+			| -(으)ㄹ걸요 | guess, "I bet" | 벌써 갔**을걸요**. — He's probably gone already. |
+			| -더라고요 | reporting what you saw (B2) | 사람이 많**더라고요**. |
+		`,
+			words: `
+			-잖아요 | you know (shared knowledge)
+			-거든요 | you see (explanation)
+			-네요 | oh! (discovery)
+			-군요 | I see (realization)
+			-죠 | right? (agreement)
+			-(으)ㄹ걸요 | I bet; probably
+			벌써 | already
+			아직 | still; yet
+			그러니까 | so; that is why
+			역시 | as expected
+		`,
+			sentences: `
+			제가 어제 말했잖아요. | I told you yesterday, you know.
+			오늘은 못 가요. 약속이 있거든요. | I can't go today. I have plans, you see.
+			와, 한국어를 정말 잘하시네요! | Wow, you speak Korean really well!
+			아, 그래서 늦었군요. | Ah, so that's why you were late.
+			이 노래 좋죠? | This song is good, right?
+			지금 가면 벌써 끝났을걸요. | If we go now, it'll probably be over already.
+			역시 집이 최고예요. | As expected, home is the best.
+		`,
+			drills: `
+			(explaining to someone who didn't know) I'm sick, you see: 아프___ | 거든요 | 잖아요; 네요; 군요
+			(reminding) It's Sunday, you know: 일요일이___ | 잖아요 | 거든요; 네요; 걸요
+			(surprised discovery) Oh, it's snowing!: 눈이 오___ | 네요 | 잖아요; 거든요; 죠
+			It's hot, right?: 덥___ | 죠 | 거든요; 네요; 걸요
+		`
+		}),
+		lesson({
+			id: 'ko-abstract',
+			title: '추상 어휘',
+			summary: 'Abstract vocabulary for discussion',
+			notes: `
+			Useful phrases for giving structured opinions:
+			- **제 생각에는 …** — In my opinion …
+			- **…에 대해(서)** — about …: *이 문제에 대해서 어떻게 생각하세요?*
+			- **…에 따라** — depending on …: *사람에 따라 달라요.*
+			- **…(으)ㄹ 수밖에 없다** — have no choice but to …
+			- **…다고 볼 수 있다** — it can be seen that …
+			- **반면에 / 한편으로는** — on the other hand
+		`,
+			words: `
+			개념 | concept
+			관점 | point of view
+			영향 | influence
+			원인 | cause
+			결과 | result
+			문제점 | problem; drawback
+			해결책 | solution
+			발전 | development
+			경쟁 | competition
+			가치관 | values
+			세대 차이 | generation gap
+			인식 | perception; awareness
+			-에 대해서 | about
+			-에 따라 | depending on
+			-(으)ㄹ 수밖에 없다 | to have no choice but to
+		`,
+			sentences: `
+			이 문제에 대해서 어떻게 생각하세요? | What do you think about this problem?
+			제 생각에는 해결책이 필요해요. | In my opinion, we need a solution.
+			사람에 따라 가치관이 달라요. | Values differ from person to person.
+			세대 차이 때문에 갈등이 생겨요. | Conflicts arise because of the generation gap.
+			경쟁이 심해서 스트레스를 받을 수밖에 없어요. | Competition is so fierce that you can't help being stressed.
+			기술 발전은 사회에 큰 영향을 미쳤어요. | Technological development has had a big influence on society.
+		`,
+			drills: `
+			solution | 해결책 | 문제점; 원인; 결과
+			point of view | 관점 | 개념; 인식; 영향
+			depending on the person: 사람___ | 에 따라 | 에 대해서; 때문에; 밖에
+			to have a big influence: 큰 영향을 ___ | 미치다 | 하다; 되다; 나다
+		`
+		}),
+		lesson({
+			id: 'ko-four-char',
+			title: '사자성어',
+			summary: 'Four-character idioms',
+			notes: `
+			**사자성어** are four-syllable idioms from Classical Chinese, common in speeches, news and among educated speakers.
+
+			| idiom | literally | meaning |
+			|---|---|---|
+			| 일석이조 (一石二鳥) | one stone, two birds | killing two birds with one stone |
+			| 작심삼일 (作心三日) | resolution for three days | resolutions that don't last |
+			| 이심전심 (以心傳心) | from heart to heart | unspoken understanding |
+			| 우왕좌왕 (右往左往) | going right, going left | running around in confusion |
+			| 동문서답 (東問西答) | east question, west answer | an irrelevant answer |
+			| 대기만성 (大器晩成) | great vessels are finished late | late bloomer |
+			| 자업자득 (自業自得) | reap what you sow | you brought it on yourself |
+			| 금시초문 (今時初聞) | first hearing now | news to me |
+			| 십중팔구 (十中八九) | eight or nine out of ten | most likely |
+			| 유비무환 (有備無患) | prepared, no worries | better safe than sorry |
+		`,
+			words: `
+			사자성어 | four-character idiom
+			일석이조 | two birds with one stone
+			작심삼일 | a resolution that lasts three days
+			이심전심 | unspoken understanding
+			우왕좌왕 | running around in confusion
+			동문서답 | an irrelevant answer
+			대기만성 | a late bloomer
+			자업자득 | you reap what you sow
+			금시초문 | news to me
+			십중팔구 | most likely
+			유비무환 | better safe than sorry
+		`,
+			sentences: `
+			운동하면서 영어 공부도 하니까 일석이조예요. | Exercising while studying English: two birds with one stone.
+			다이어트는 항상 작심삼일이에요. | My diets never last more than three days.
+			그건 금시초문인데요. | That's news to me.
+			십중팔구 비가 올 거예요. | It will most likely rain.
+			유비무환이니까 우산을 챙기세요. | Better safe than sorry, so bring an umbrella.
+			그 사람은 늘 동문서답을 해요. | That person always gives irrelevant answers.
+		`,
+			drills: `
+			New Year's resolutions that fail after three days: | 작심삼일 | 일석이조; 대기만성; 유비무환
+			Two birds with one stone: | 일석이조 | 이심전심; 십중팔구; 자업자득
+			"That's news to me": | 금시초문 | 동문서답; 우왕좌왕; 작심삼일
+			Most likely (8 or 9 out of 10): | 십중팔구 | 일석이조; 유비무환; 대기만성
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/hangul.ts

@@ -0,0 +1,334 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'hangul',
+	'Hangul',
+	'The alphabet',
+	'Learn to read Korean in five short lessons. Everything after this is written in Hangul.',
+	[
+		lesson({
+			id: 'ko-vowels',
+			title: 'Basic vowels',
+			summary: 'ㅏ ㅓ ㅗ ㅜ ㅡ ㅣ and how syllables are built',
+			notes: `
+			Hangul was invented in 1443 by King Sejong so that anyone could learn to read. It has 24 basic letters, grouped into **syllable blocks**.
+
+			Every block starts with a consonant. If a syllable starts with a vowel sound, it uses the silent **ㅇ** as a placeholder: **아** = ㅇ + ㅏ = "a".
+
+			| letter | sound | block |
+			|---|---|---|
+			| ㅏ | a (father) | 아 |
+			| ㅓ | eo (like "u" in "up") | 어 |
+			| ㅗ | o (more rounded) | 오 |
+			| ㅜ | u (food) | 우 |
+			| ㅡ | eu (unrounded "oo", lips flat) | 으 |
+			| ㅣ | i (see) | 이 |
+
+			**Vertical** vowels (ㅏ ㅓ ㅣ) go to the **right** of the consonant: 아, 어, 이.
+			**Horizontal** vowels (ㅗ ㅜ ㅡ) go **below** it: 오, 우, 으.
+		`,
+			script: `
+			ㅏ | a
+			ㅓ | eo | like the u in "up"
+			ㅗ | o
+			ㅜ | u
+			ㅡ | eu | lips spread, like a flat "oo"
+			ㅣ | i
+			아 | a
+			어 | eo
+			오 | o
+			우 | u
+			으 | eu
+			이 | i
+		`,
+			words: `
+			아이 | child
+			오이 | cucumber
+			이 | two; tooth
+			오 | five
+		`,
+			drills: `
+			Which vowel goes below the consonant? | ㅗ | ㅏ; ㅓ; ㅣ | Horizontal vowels go below.
+			What does ㅇ sound like at the start of a syllable? | nothing (silent) | ng; o; h
+			How is 어 read? | eo | a; o; u
+			How is 으 read? | eu | u; o; i
+		`
+		}),
+		lesson({
+			id: 'ko-consonants',
+			title: 'Basic consonants',
+			summary: 'ㄱ ㄴ ㄷ ㄹ ㅁ ㅂ ㅅ ㅇ ㅈ ㅎ',
+			notes: `
+			The consonant shapes show the mouth: **ㄱ** is the tongue touching the back of the mouth, **ㄴ** the tongue on the ridge behind the teeth, **ㅁ** the closed lips.
+
+			| letter | sound | example |
+			|---|---|---|
+			| ㄱ | g / k | 가 ga |
+			| ㄴ | n | 나 na |
+			| ㄷ | d / t | 다 da |
+			| ㄹ | r / l | 라 ra |
+			| ㅁ | m | 마 ma |
+			| ㅂ | b / p | 바 ba |
+			| ㅅ | s (sh before ㅣ) | 사 sa, 시 si |
+			| ㅇ | silent / ng | 아 a |
+			| ㅈ | j | 자 ja |
+			| ㅎ | h | 하 ha |
+
+			ㄱ ㄷ ㅂ ㅈ sound softer than English k t p ch: somewhere between g/k, d/t, b/p.
+			ㄹ is a quick flap between r and l, like the "tt" in American "butter".
+		`,
+			script: `
+			ㄱ | g; k
+			ㄴ | n
+			ㄷ | d; t
+			ㄹ | r; l
+			ㅁ | m
+			ㅂ | b; p
+			ㅅ | s
+			ㅈ | j
+			ㅎ | h
+			가 | ga
+			나 | na
+			다 | da
+			라 | ra
+			마 | ma
+			바 | ba
+			사 | sa
+			자 | ja
+			하 | ha
+			고 | go
+			두 | du
+			미 | mi
+		`,
+			words: `
+			나라 | country
+			나무 | tree
+			바다 | sea
+			모자 | hat
+			어머니 | mother
+			아버지 | father
+			가수 | singer
+			하나 | one
+			두부 | tofu
+			지도 | map
+			누나 | older sister (said by a male)
+			라디오 | radio
+		`,
+			sentences: `
+			어머니 아버지 | mother and father
+		`,
+			drills: `
+			How is 나무 read? | namu | nabu; lamu; namo
+			How is 바다 read? | bada | pata; bara; mada
+			Which letter is "m"? | ㅁ | ㅂ; ㄴ; ㅇ
+			Which letter is the r/l sound? | ㄹ | ㄷ; ㄴ; ㅎ
+		`
+		}),
+		lesson({
+			id: 'ko-strong-consonants',
+			title: 'Aspirated and tense consonants',
+			summary: 'ㅋ ㅌ ㅍ ㅊ and ㄲ ㄸ ㅃ ㅆ ㅉ',
+			notes: `
+			Adding a stroke makes a consonant **aspirated** (with a puff of air). Doubling it makes it **tense** (no air, tight throat).
+
+			| plain | aspirated | tense |
+			|---|---|---|
+			| ㄱ g | ㅋ k | ㄲ kk |
+			| ㄷ d | ㅌ t | ㄸ tt |
+			| ㅂ b | ㅍ p | ㅃ pp |
+			| ㅈ j | ㅊ ch | ㅉ jj |
+			| ㅅ s | | ㅆ ss |
+
+			Hold a hand in front of your mouth: **카** should give a strong puff, **까** almost none (like the k in "skate").
+
+			These three-way contrasts change meaning: **불** (fire), **풀** (grass), **뿔** (horn).
+		`,
+			script: `
+			ㅋ | k
+			ㅌ | t
+			ㅍ | p
+			ㅊ | ch
+			ㄲ | kk
+			ㄸ | tt
+			ㅃ | pp
+			ㅆ | ss
+			ㅉ | jj
+			카 | ka
+			타 | ta
+			파 | pa
+			차 | cha
+			까 | kka
+			따 | tta
+			빠 | ppa
+			싸 | ssa
+			짜 | jja
+		`,
+			words: `
+			커피 | coffee
+			차 | tea; car
+			토마토 | tomato
+			피자 | pizza
+			아빠 | dad
+			오빠 | older brother (said by a female)
+			코 | nose
+			치마 | skirt
+			토끼 | rabbit
+			기차 | train
+			머리 | head; hair
+			아저씨 | mister; middle-aged man
+		`,
+			sentences: `
+			커피 주세요 | Coffee, please.
+		`,
+			drills: `
+			Which one is aspirated (with a puff of air)? | ㅋ | ㄲ; ㄱ; ㅇ
+			Which one is tense? | ㄸ | ㅌ; ㄷ; ㄹ
+			How is 아빠 read? | appa | aba; apa; abba
+			How is 치마 read? | chima | jima; kima; tima
+			How is 토끼 read? | tokki | dogi; toki; tokgi
+		`
+		}),
+		lesson({
+			id: 'ko-compound-vowels',
+			title: 'More vowels',
+			summary: 'ㅐ ㅔ, the y-vowels and the w-vowels',
+			notes: `
+			**One extra stroke adds a "y"**: ㅏ → ㅑ (ya), ㅓ → ㅕ (yeo), ㅗ → ㅛ (yo), ㅜ → ㅠ (yu).
+
+			**ㅐ (ae)** and **ㅔ (e)** sound almost the same today (both like "e" in "bed"). ㅒ (yae) and ㅖ (ye) likewise.
+
+			**W-vowels** combine ㅗ or ㅜ with another vowel:
+			| | | |
+			|---|---|---|
+			| ㅘ = ㅗ+ㅏ | wa | 와 |
+			| ㅙ = ㅗ+ㅐ | wae | 왜 |
+			| ㅚ = ㅗ+ㅣ | oe (said "we") | 외 |
+			| ㅝ = ㅜ+ㅓ | wo | 워 |
+			| ㅞ = ㅜ+ㅔ | we | 웨 |
+			| ㅟ = ㅜ+ㅣ | wi | 위 |
+			| ㅢ = ㅡ+ㅣ | ui | 의 |
+
+			**ㅢ** is read "ui" at the start of a word, "i" after a consonant (희 = hi), and "e" as the possessive particle 의.
+		`,
+			script: `
+			ㅐ | ae
+			ㅔ | e
+			ㅑ | ya
+			ㅕ | yeo
+			ㅛ | yo
+			ㅠ | yu
+			ㅘ | wa
+			ㅝ | wo
+			ㅟ | wi
+			ㅢ | ui
+			ㅚ | oe
+			ㅙ | wae
+			애 | ae
+			에 | e
+			야 | ya
+			여 | yeo
+			요 | yo
+			유 | yu
+			와 | wa
+			워 | wo
+			위 | wi
+			의 | ui
+			왜 | wae
+		`,
+			words: `
+			우유 | milk
+			여우 | fox
+			요리 | cooking
+			개 | dog
+			게 | crab
+			사과 | apple
+			돼지 | pig
+			의자 | chair
+			회사 | company
+			뭐 | what
+			귀 | ear
+			야구 | baseball
+			왜 | why
+			세계 | world
+		`,
+			sentences: `
+			우유 주세요 | Milk, please.
+			이게 뭐예요? | What is this?
+		`,
+			drills: `
+			Adding a stroke to ㅏ gives: | ㅑ | ㅐ; ㅓ; ㅘ
+			ㅗ + ㅏ = | ㅘ | ㅝ; ㅚ; ㅙ
+			How is 의자 read? | uija | euija; wija; eja
+			How is 돼지 read? | dwaeji | doeji; dweji; dwaji
+			How is 여우 read? | yeou | yau; yeowu; yoou
+		`
+		}),
+		lesson({
+			id: 'ko-batchim',
+			title: 'Final consonants (batchim)',
+			summary: 'Consonants at the bottom of a block and how they link',
+			notes: `
+			A consonant at the bottom of a block is a **batchim** (받침). Whatever the letter, a final consonant is pronounced as one of **seven sounds**:
+
+			| sound | letters | example |
+			|---|---|---|
+			| k | ㄱ ㅋ ㄲ | 책 chaek, 부엌 bueok |
+			| n | ㄴ | 산 san |
+			| t | ㄷ ㅌ ㅅ ㅆ ㅈ ㅊ ㅎ | 옷 ot, 꽃 kkot |
+			| l | ㄹ | 물 mul |
+			| m | ㅁ | 밤 bam |
+			| p | ㅂ ㅍ | 밥 bap, 앞 ap |
+			| ng | ㅇ | 강 gang |
+
+			### Linking (연음)
+			If the next syllable starts with the silent **ㅇ**, the batchim **moves over** and is pronounced in full:
+			- 한국어 → [한구거] **hangugeo**
+			- 음악 → [으막] **eumak**
+			- 옷이 → [오시] **osi**
+
+			### Nasalization
+			A k/t/p sound before ㄴ or ㅁ becomes ng/n/m: **감사합니다** → [감사함니다] **gamsahamnida**.
+		`,
+			script: `
+			각 | gak
+			간 | gan
+			갈 | gal
+			감 | gam
+			갑 | gap
+			강 | gang
+			옷 | ot
+			밖 | bak
+			앞 | ap
+			꽃 | kkot
+		`,
+			words: `
+			한국 | Korea
+			사람 | person
+			물 | water
+			밥 | rice; meal
+			책 | book
+			빵 | bread
+			김치 | kimchi
+			선생님 | teacher
+			학생 | student
+			음식 | food
+			옷 | clothes
+			꽃 | flower
+			서울 | Seoul
+			한국어 | Korean (language)
+			음악 | music
+		`,
+			sentences: `
+			감사합니다 | Thank you.
+			한국 사람 | a Korean person
+		`,
+			drills: `
+			The final ㅅ in 옷 sounds like: | t | s; ch; sh
+			The final ㅂ in 밥 sounds like: | p | b; m; silent
+			How is 음악 read? | eumak | eum-ak; eumag; umak | The ㅁ links to the next syllable.
+			How is 감사합니다 read? | gamsahamnida | gamsahapnida; kamsahabnida; gamsahabnida | ㅂ before ㄴ becomes m.
+			How is 한국어 read? | hangugeo | hanguk-eo; hangukeo; hangukgeo
+		`
+		})
+	]
+);

src/lib/language-learner/courses/ko/index.ts

@@ -0,0 +1,19 @@
+import { course } from '../../course';
+import hangul from './hangul';
+import a1 from './a1';
+import a2 from './a2';
+import b1 from './b1';
+import b2 from './b2';
+import c1 from './c1';
+
+export default course(
+	{
+		code: 'ko',
+		name: 'Korean',
+		nativeName: '한국어',
+		glossLang: 'en',
+		voice: 'ko-KR',
+		tagline: 'Hangul first, then grammar and speech levels, taught in English.'
+	},
+	[hangul, a1, a2, b1, b2, c1]
+);

src/lib/language-learner/courses/nl/a1.ts

@@ -0,0 +1,558 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a1',
+	'A1',
+	'Beginner',
+	'Greetings, introducing yourself, numbers, family, food and getting around.',
+	[
+		lesson({
+			id: 'nl-hallo',
+			title: 'Hallo!',
+			summary: 'Greetings, goodbyes and the sounds of Dutch',
+			notes: `
+			Dutch greetings change with the time of day. **Hoi** and **hallo** work any time; **dag** is both hello and goodbye.
+
+			| Dutch | When |
+			|---|---|
+			| goedemorgen | until about 12:00 |
+			| goedemiddag | 12:00–18:00 |
+			| goedenavond | evening |
+			| welterusten | good night (going to sleep) |
+
+			### Sounds to know
+			- **g** and **ch** are the same throaty sound, like clearing your throat softly: *goed*, *acht*.
+			- **ui** has no English equivalent: round your lips and say "ow" (*huis*, *uit*).
+			- **ij** and **ei** sound the same, close to the "ay" in "day": *mij*, *klein*.
+			- **oe** is "oo" as in "food": *goed*. **eu** is like French *peu*: *leuk*.
+			- A double vowel is long: *maan* (moon) vs *man* (man).
+			- **w** is softer than in English, between English w and v.
+
+			**Alsjeblieft** means both "please" and "here you are". Use **alstublieft** in formal situations.
+		`,
+			words: `
+			hallo; hoi | hello; hi
+			dag | bye; hello | Works for both, a little formal
+			doei | bye | Casual
+			goedemorgen | good morning
+			goedemiddag | good afternoon
+			goedenavond | good evening
+			welterusten | good night | Only when someone goes to sleep
+			tot ziens | goodbye; see you
+			tot straks | see you later (today)
+			alsjeblieft | please; here you are | Informal; formal: alstublieft
+			dank je wel; dankjewel | thank you (very much) | Formal: dank u wel
+			bedankt | thanks
+			graag gedaan | you're welcome
+			ja | yes
+			nee | no
+			sorry | sorry
+			pardon | excuse me
+		`,
+			sentences: `
+			Hoi, hoe gaat het? | Hi, how are you?
+			Goed, dank je. | Good, thanks.
+			Met mij gaat het goed. | I'm doing well.
+			Tot morgen! | See you tomorrow!
+			Hoe gaat het met u? | How are you? (formal)
+			Een koffie, alsjeblieft. | A coffee, please.
+			Dank je wel, tot ziens! | Thank you, goodbye!
+		`,
+			drills: `
+			It is 09:00. You say: ___ | goedemorgen | goedenavond; welterusten; goedemiddag
+			It is 20:00 and you arrive at a party: ___ | goedenavond | welterusten; goedemorgen; goedemiddag
+			Your friend goes to bed. You say: ___ | welterusten | goedenavond; tot ziens; goedemorgen
+			Someone thanks you. You say: ___ | graag gedaan | alsjeblieft; sorry; pardon | Graag gedaan = "gladly done"
+			You hand someone their change: ___ | alsjeblieft | dank je; graag gedaan; pardon | Alsjeblieft also means "here you are".
+		`
+		}),
+		lesson({
+			id: 'nl-wie',
+			title: 'Wie ben jij?',
+			summary: 'Pronouns, zijn and hebben, introducing yourself',
+			notes: `
+			### Personal pronouns
+			| | singular | plural |
+			|---|---|---|
+			| 1st | ik | wij / we |
+			| 2nd | jij / je (informal), u (formal) | jullie |
+			| 3rd | hij, zij / ze, het | zij / ze |
+
+			**Je**, **we** and **ze** are the unstressed forms and are the ones you hear most.
+
+			### zijn (to be) and hebben (to have)
+			| | zijn | hebben |
+			|---|---|---|
+			| ik | ben | heb |
+			| jij / je | bent | hebt |
+			| u | bent | hebt / heeft |
+			| hij / zij / het | is | heeft |
+			| wij / jullie / zij | zijn | hebben |
+
+			In a question the verb moves before the subject, and **jij** loses its -t: *jij bent* → *ben jij?*, *jij hebt* → *heb jij?*
+		`,
+			words: `
+			ik | I
+			jij; je | you (informal)
+			u | you (formal)
+			hij | he
+			zij; ze | she; they
+			wij; we | we
+			jullie | you (plural)
+			de naam | the name
+			heten | to be called
+			komen uit | to come from
+			wonen | to live (somewhere)
+			Nederland | the Netherlands
+			België | Belgium
+			Nederlands | Dutch (language)
+			Engels | English (language)
+		`,
+			sentences: `
+			Ik heet Stan. | My name is Stan.
+			Wat is jouw naam? | What is your name?
+			Ik ben student. | I am a student.
+			Waar kom je vandaan? | Where are you from?
+			Ik kom uit Nederland. | I come from the Netherlands.
+			Ik woon in Amsterdam. | I live in Amsterdam.
+			Hij heeft een broer. | He has a brother.
+			Wij zijn vrienden. | We are friends.
+			Spreekt u Engels? | Do you speak English?
+		`,
+			drills: `
+			Ik ___ student. | ben | bent; is; zijn
+			Jij ___ mijn vriend. | bent | ben; is; zijn
+			Zij ___ uit België. (komen, she) | komt | kom; komen; kome
+			Wij ___ een hond. | hebben | heb; hebt; heeft
+			Hij ___ een auto. | heeft | hebt; heb; hebben
+			___ jij Nederlands? (to speak) | Spreek | Spreekt; Spreken; Spreke | Inverted jij drops the -t.
+			Jullie ___ in Utrecht. (to live) | wonen | woont; woon; wonent
+		`
+		}),
+		lesson({
+			id: 'nl-getallen',
+			title: 'Getallen',
+			summary: 'Numbers 0–100, age and phone numbers',
+			notes: `
+			| | | | |
+			|---|---|---|---|
+			| 0 nul | 5 vijf | 10 tien | 15 vijftien |
+			| 1 een | 6 zes | 11 elf | 16 zestien |
+			| 2 twee | 7 zeven | 12 twaalf | 17 zeventien |
+			| 3 drie | 8 acht | 13 dertien | 18 achttien |
+			| 4 vier | 9 negen | 14 veertien | 19 negentien |
+
+			Tens: twintig, dertig, veertig, vijftig, zestig, zeventig, tachtig, negentig.
+
+			From 21 the **unit comes first**, linked by *en*, all written as one word: **eenentwintig** (one-and-twenty), **vijfenveertig** (45).
+			After a word ending in -e you write **ën**: *tweeëntwintig*, *drieëndertig*.
+
+			**Hoe oud ben je?** — *Ik ben vijfentwintig (jaar).*
+
+			When "one" is stressed it is written **één**, to tell it apart from the article *een* (a).
+		`,
+			words: `
+			nul | zero
+			een; één | one
+			twee | two
+			drie | three
+			vier | four
+			vijf | five
+			zes | six
+			zeven | seven
+			acht | eight
+			negen | nine
+			tien | ten
+			elf | eleven
+			twaalf | twelve
+			twintig | twenty
+			dertig | thirty
+			veertig | forty
+			vijftig | fifty
+			honderd | hundred
+			oud | old
+		`,
+			sentences: `
+			Hoe oud ben je? | How old are you?
+			Ik ben eenentwintig jaar. | I am twenty-one years old.
+			Mijn moeder is vijfenvijftig. | My mother is fifty-five.
+			Wat is je telefoonnummer? | What is your phone number?
+			Ik heb twee katten. | I have two cats.
+			Het kost tien euro. | It costs ten euros.
+		`,
+			drills: `
+			34 | vierendertig | drieënveertig; dertigvier; vierdertig | Unit first: four-and-thirty.
+			22 | tweeëntwintig | twintigtwee; tweeentwintig; tweetwintig | Two e's meet: write ë.
+			80 | tachtig | achtig; achttig; achtentig
+			47 | zevenenveertig | vierenzeventig; veertigzeven; zevenveertig
+			13 | dertien | drieën; drietien; dertig
+		`
+		}),
+		lesson({
+			id: 'nl-familie',
+			title: 'De familie',
+			summary: 'Family members, de and het, possessives',
+			notes: `
+			### De and het
+			Dutch has two words for "the": **de** and **het**. About two thirds of nouns take *de*.
+
+			- **Plurals always take de**: *het kind* → *de kinderen*.
+			- People are almost always *de* (*de moeder*, *de broer*). Exception: *het kind*, *het meisje*.
+			- **Diminutives (-je) are always het**: *het huisje*, *het meisje*.
+			- Otherwise: learn every noun with its article.
+
+			"A/an" is always **een** (pronounced like "un").
+
+			### Possessives
+			| | |
+			|---|---|
+			| mijn | my |
+			| jouw / je | your |
+			| uw | your (formal) |
+			| zijn | his |
+			| haar | her |
+			| ons / onze | our |
+			| jullie | your (plural) |
+			| hun | their |
+
+			**Ons** is used with *het* words (*ons huis*), **onze** with *de* words and plurals (*onze moeder*, *onze kinderen*).
+		`,
+			words: `
+			de familie | the (extended) family
+			het gezin | the family (household)
+			de moeder | the mother
+			de vader | the father
+			de ouders | the parents
+			de zus | the sister
+			de broer | the brother
+			het kind | the child
+			de kinderen | the children
+			de zoon | the son
+			de dochter | the daughter
+			de oma | the grandma
+			de opa | the grandpa
+			de man | the man; the husband
+			de vrouw | the woman; the wife
+			het meisje | the girl
+			de jongen | the boy
+			getrouwd | married
+		`,
+			sentences: `
+			Dit is mijn moeder. | This is my mother.
+			Heb je broers of zussen? | Do you have brothers or sisters?
+			Ik heb een zus en twee broers. | I have a sister and two brothers.
+			Onze ouders wonen in Groningen. | Our parents live in Groningen.
+			Zijn vrouw heet Anna. | His wife is called Anna.
+			Het kind is drie jaar oud. | The child is three years old.
+			Ons huis is klein. | Our house is small.
+		`,
+			drills: `
+			___ meisje | het | de | Words ending in -je are het.
+			___ moeder | de | het
+			___ kind | het | de
+			___ kinderen | de | het | Plurals are always de.
+			___ huis is groot. (our) | Ons | Onze | Huis is a het-word.
+			___ kinderen zijn thuis. (our) | Onze | Ons | Plurals take onze.
+			Dit is ___ broer. (her) | haar | hun; zijn; hij
+		`
+		}),
+		lesson({
+			id: 'nl-eten',
+			title: 'Eten en drinken',
+			summary: 'Food, drink, and regular verbs in the present',
+			notes: `
+			### The present tense
+			Take the infinitive, remove **-en**: that is the **stem** and the *ik* form.
+
+			| werken (to work) | |
+			|---|---|
+			| ik | werk |
+			| jij / u / hij / zij | werk**t** |
+			| wij / jullie / zij | werk**en** |
+
+			Spelling rules keep the sound the same:
+			- A long vowel in an open syllable is written double in the stem: *maken* → *ik maak*, *eten* → *ik eet*.
+			- A doubled consonant becomes single: *zitten* → *ik zit*, *bakken* → *ik bak*.
+			- Dutch words never end in **v** or **z**: *leven* → *ik leef*, *lezen* → *ik lees*.
+			- A stem ending in **t** doesn't get an extra t: *ik zit*, *hij zit*.
+
+			**Lekker** (tasty, nice) is one of the most used Dutch words: *Eet smakelijk!* is "enjoy your meal".
+		`,
+			words: `
+			eten | to eat
+			drinken | to drink
+			het brood | the bread
+			de kaas | the cheese
+			de boter | the butter
+			het ei | the egg
+			de appel | the apple
+			het water | the water
+			de koffie | the coffee
+			de thee | the tea
+			de melk | the milk
+			het bier | the beer
+			de hagelslag | chocolate sprinkles
+			het ontbijt | the breakfast
+			de lunch | the lunch
+			het avondeten | the dinner
+			lekker | tasty; nice
+			de honger | hunger
+			de dorst | thirst
+		`,
+			sentences: `
+			Ik heb honger. | I am hungry.
+			Heb jij dorst? | Are you thirsty?
+			Ik eet een broodje kaas. | I'm eating a cheese sandwich.
+			Hij drinkt koffie met melk. | He drinks coffee with milk.
+			Wij eten om zes uur. | We eat at six o'clock.
+			Dat is lekker! | That is tasty!
+			Eet smakelijk! | Enjoy your meal!
+			Mag ik een glas water? | May I have a glass of water?
+		`,
+			drills: `
+			Ik ___ graag kaas. (eten) | eet | eten; eett; et
+			Jij ___ veel thee. (drinken) | drinkt | drink; drinken; drinkte
+			Hij ___ in Leiden. (wonen) | woont | wont; woon; wonen | Long vowel written double: woon-t.
+			Wij ___ een taart. (bakken) | bakken | bakt; bak; baken
+			Ik ___ een boek. (lezen) | lees | leez; lez; lezen | No word ends in z: lezen → lees.
+			Zij ___ op de bank. (zitten, she) | zit | zitt; zitten; zits | A stem ending in t gets no extra t.
+		`
+		}),
+		lesson({
+			id: 'nl-vragen',
+			title: 'Vragen stellen',
+			summary: 'Question words and word order in questions',
+			notes: `
+			### Question words
+			| | |
+			|---|---|
+			| wie | who |
+			| wat | what |
+			| waar | where |
+			| waarheen / waar … naartoe | where to |
+			| wanneer | when |
+			| waarom | why |
+			| hoe | how |
+			| hoeveel | how much / many |
+			| welk / welke | which |
+
+			**Welk** goes with singular het-words (*welk huis*), **welke** with everything else (*welke auto*, *welke huizen*).
+
+			### Word order
+			Yes/no questions start with the verb: *Woon je hier?*
+			With a question word, the verb comes second: *Waar woon je?*
+
+			Remember: **jij/je** after the verb loses its -t: *Werk jij morgen?*
+		`,
+			words: `
+			wie | who
+			wat | what
+			waar | where
+			wanneer | when
+			waarom | why
+			hoe | how
+			hoeveel | how much; how many
+			welke | which
+			omdat | because
+			hier | here
+			daar | there
+			nu | now
+			vandaag | today
+			morgen | tomorrow; morning
+		`,
+			sentences: `
+			Wie is dat? | Who is that?
+			Wat doe je? | What are you doing?
+			Waar is het station? | Where is the station?
+			Wanneer begint de film? | When does the film start?
+			Waarom lach je? | Why are you laughing?
+			Hoeveel kost dit? | How much does this cost?
+			Welke trein gaat naar Den Haag? | Which train goes to The Hague?
+			Werk jij morgen? | Are you working tomorrow?
+		`,
+			drills: `
+			___ kost een kaartje? | Hoeveel | Hoe; Waar; Wie
+			___ woon je? – In Delft. | Waar | Wanneer; Wie; Wat
+			___ huis is van jou? | Welk | Welke | Huis is a het-word, singular: welk.
+			___ fiets is van jou? | Welke | Welk | Fiets is a de-word: welke.
+			___ jij morgen? (werken) | Werk | Werkt; Werken; Werkte | Inversion: werk jij.
+			___ ben je laat? – Omdat de trein laat was. | Waarom | Wanneer; Hoe; Wat
+		`
+		}),
+		lesson({
+			id: 'nl-tijd',
+			title: 'Dagen en tijd',
+			summary: 'Days of the week, months and telling time',
+			notes: `
+			Days and months are written **without a capital** in Dutch.
+
+			### Telling time: the "half" trap
+			Dutch counts half hours **towards** the next hour:
+
+			| time | Dutch |
+			|---|---|
+			| 2:00 | twee uur |
+			| 2:15 | kwart over twee |
+			| **2:30** | **half drie** (half *to* three) |
+			| 2:45 | kwart voor drie |
+			| 2:20 | tien voor half drie |
+			| 2:35 | vijf over half drie |
+
+			**Hoe laat is het?** — What time is it? **Om hoe laat?** — At what time?
+			In schedules the 24-hour clock is used: *om 14.30 uur* (veertien uur dertig).
+		`,
+			words: `
+			maandag | Monday
+			dinsdag | Tuesday
+			woensdag | Wednesday
+			donderdag | Thursday
+			vrijdag | Friday
+			zaterdag | Saturday
+			zondag | Sunday
+			het weekend | the weekend
+			de week | the week
+			de maand | the month
+			het jaar | the year
+			het uur | the hour; o'clock
+			de minuut | the minute
+			het kwartier | the quarter of an hour
+			half | half
+			gisteren | yesterday
+			vroeg | early
+			laat | late
+		`,
+			sentences: `
+			Hoe laat is het? | What time is it?
+			Het is half acht. | It is half past seven.
+			De les begint om kwart over negen. | The lesson starts at a quarter past nine.
+			Ik werk van maandag tot vrijdag. | I work from Monday to Friday.
+			Op zaterdag slaap ik lang. | On Saturday I sleep in.
+			Tot volgende week! | See you next week!
+			Ik ben te laat. | I am too late.
+		`,
+			drills: `
+			3:30 = ___ | half vier | half drie; drie en half; half over drie | Half counts towards the next hour.
+			9:15 = ___ | kwart over negen | kwart voor negen; kwart over tien; half negen
+			6:45 = ___ | kwart voor zeven | kwart over zeven; kwart voor zes; half zeven
+			11:25 = ___ | vijf voor half twaalf | vijf over half twaalf; vijf voor half elf; vijfentwintig over elf
+			The day after dinsdag: ___ | woensdag | donderdag; maandag; vrijdag
+		`
+		}),
+		lesson({
+			id: 'nl-stad',
+			title: 'In de stad',
+			summary: 'Places, directions, and er is / er zijn',
+			notes: `
+			### Er is / er zijn
+			To say something exists somewhere, use **er is** (singular) or **er zijn** (plural):
+			- *Er is een bakker in de straat.* — There is a baker in the street.
+			- *Er zijn veel fietsen.* — There are a lot of bikes.
+
+			### Directions
+			| | |
+			|---|---|
+			| rechtdoor | straight on |
+			| linksaf / naar links | (turn) left |
+			| rechtsaf / naar rechts | (turn) right |
+			| de eerste straat | the first street |
+			| op de hoek | on the corner |
+			| tegenover | opposite |
+
+			**Gaan + naar** = go to: *Ik ga naar het station.* **Bij** = at (someone's place / a shop): *bij de bakker*.
+		`,
+			words: `
+			de stad | the city
+			de straat | the street
+			het station | the station
+			de winkel | the shop
+			de supermarkt | the supermarket
+			de bakker | the baker
+			de bank | the bank; the couch
+			het plein | the square
+			de brug | the bridge
+			de gracht | the canal
+			de fiets | the bicycle
+			links | left
+			rechts | right
+			rechtdoor | straight on
+			ver | far
+			dichtbij | close by
+			de hoek | the corner
+		`,
+			sentences: `
+			Waar is de supermarkt? | Where is the supermarket?
+			Ga hier linksaf. | Turn left here.
+			Het station is dichtbij. | The station is close by.
+			Er is een bakker op de hoek. | There is a baker on the corner.
+			Er zijn veel fietsen in Amsterdam. | There are a lot of bikes in Amsterdam.
+			Ik ga met de fiets naar de stad. | I'm going into town by bike.
+			Is het ver? | Is it far?
+		`,
+			drills: `
+			Er ___ een museum in de stad. | is | zijn; heeft; hebben
+			Er ___ twee bakkers in deze straat. | zijn | is; hebben; heeft
+			Ik ga ___ het station. | naar | bij; in; op
+			Ik koop brood ___ de bakker. | bij | naar; aan; met
+			Ik ga ___ de fiets. | met | op; in; bij | Transport uses met: met de trein, met de auto.
+		`
+		}),
+		lesson({
+			id: 'nl-kleuren',
+			title: 'Kleuren en bijvoeglijke naamwoorden',
+			summary: 'Colours, adjectives and the -e ending',
+			notes: `
+			### Adjective endings
+			Before a noun, adjectives usually get **-e**: *de rode fiets*, *het grote huis*, *een grote auto*.
+
+			The **only** exception: an **indefinite het-word in the singular** (after *een*, *geen*, or no article): *een groot huis*, *geen mooi weer*.
+
+			| | de-word | het-word |
+			|---|---|---|
+			| the … | de grote auto | het grote huis |
+			| a … | een grote auto | een **groot** huis |
+			| plural | grote auto's | grote huizen |
+
+			After the verb (*zijn*, *worden*), there is no ending: *Het huis is groot.*
+
+			Spelling changes: *groot → grote* (long vowel in open syllable: one letter), *wit → witte* (short vowel: double consonant), *lief → lieve*, *grijs → grijze*.
+		`,
+			words: `
+			rood | red
+			blauw | blue
+			geel | yellow
+			groen | green
+			zwart | black
+			wit | white
+			oranje | orange
+			grijs | grey
+			bruin | brown
+			roze | pink
+			groot | big
+			klein | small
+			mooi | beautiful
+			lelijk | ugly
+			nieuw | new
+			duur | expensive
+			goedkoop | cheap
+			leuk | nice; fun
+		`,
+			sentences: `
+			Ik heb een rode fiets. | I have a red bicycle.
+			Het huis is groot. | The house is big.
+			Dat is een groot huis. | That is a big house.
+			De nieuwe auto is duur. | The new car is expensive.
+			Oranje is de kleur van Nederland. | Orange is the colour of the Netherlands.
+			Wat een mooi weer! | What lovely weather!
+			Ik zoek een goedkope jas. | I'm looking for a cheap coat.
+		`,
+			drills: `
+			een ___ huis (groot) | groot | grote; groote; groten | Indefinite het-word: no -e.
+			het ___ huis (groot) | grote | groot; groote; groten
+			een ___ fiets (rood) | rode | rood; roode; rooie
+			De auto is ___. (nieuw) | nieuw | nieuwe; nieuwen; nieuws | After the verb: no ending.
+			de ___ muur (wit) | witte | wite; wit; wiete | Short vowel: double the consonant.
+			een ___ kind (lief) | lief | lieve; liefe; liev | Kind is a het-word: een lief kind.
+		`
+		})
+	]
+);

src/lib/language-learner/courses/nl/a2.ts

@@ -0,0 +1,503 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'a2',
+	'A2',
+	'Elementary',
+	'Daily routines, the past, shopping, health and comparing things.',
+	[
+		lesson({
+			id: 'nl-dagelijks',
+			title: 'Mijn dag',
+			summary: 'Daily routine, separable and reflexive verbs',
+			notes: `
+			### Separable verbs
+			Many verbs have a prefix that **splits off and goes to the end** of the clause in the present and past:
+
+			- *opstaan* → *Ik sta om zeven uur **op**.*
+			- *opbellen* → *Ik bel je morgen **op**.*
+			- *meenemen* → *Neem je een jas **mee**?*
+
+			The stress is on the prefix: **op**staan, **mee**nemen. Common prefixes: *op, af, aan, uit, mee, in, terug, weg, voor*.
+
+			### Reflexive verbs
+			Some verbs need a reflexive pronoun:
+
+			| zich wassen | |
+			|---|---|
+			| ik was **me** | wij wassen **ons** |
+			| jij wast **je** | jullie wassen **je** |
+			| hij/zij wast **zich** | zij wassen **zich** |
+			| u wast **zich** | |
+
+			Common ones: *zich haasten* (hurry), *zich voelen* (feel), *zich vervelen* (be bored), *zich aankleden* (get dressed).
+		`,
+			words: `
+			opstaan | to get up
+			wakker worden | to wake up
+			zich wassen | to wash (yourself)
+			zich aankleden | to get dressed
+			ontbijten | to have breakfast
+			vertrekken | to leave
+			aankomen | to arrive
+			opbellen | to call (on the phone)
+			meenemen | to take along
+			boodschappen doen | to do the groceries
+			koken | to cook
+			afwassen | to do the dishes
+			naar bed gaan | to go to bed
+			meestal | usually
+			altijd | always
+			nooit | never
+			soms | sometimes
+			eerst | first
+			daarna | after that
+		`,
+			sentences: `
+			Ik sta om zeven uur op. | I get up at seven.
+			Daarna kleed ik me aan. | After that I get dressed.
+			Hij belt zijn moeder elke dag op. | He calls his mother every day.
+			De trein komt om negen uur aan. | The train arrives at nine.
+			Neem je een paraplu mee? | Are you taking an umbrella?
+			Ik voel me niet lekker. | I don't feel well.
+			We doen op zaterdag boodschappen. | We do the groceries on Saturday.
+			Meestal ga ik om elf uur naar bed. | I usually go to bed at eleven.
+		`,
+			drills: `
+			Ik ___ om zeven uur ___. (opstaan) | sta … op | opsta … –; sta … aan; op … sta | The prefix goes to the end.
+			Jij wast ___. | je | me; zich; ons
+			Hij voelt ___ niet goed. | zich | hem; je; me
+			Wij haasten ___. | ons | zich; we; onze
+			De bus ___ om acht uur ___. (vertrekken) | vertrekt … – | trekt … ver; vertrek … –; vertrekken … – | Ver- is not separable.
+			Morgen bel ik je ___. | op | aan; uit; mee
+		`
+		}),
+		lesson({
+			id: 'nl-voltooid',
+			title: 'Wat heb je gedaan?',
+			summary: 'The perfect tense: heb gewerkt, ben gegaan',
+			notes: `
+			The **perfect** (voltooid tegenwoordige tijd) is the usual way to talk about the past in speech:
+			**hebben / zijn + past participle** (at the end).
+
+			### Regular participles: ge- + stem + t/d
+			Use **-t** if the stem ends in one of the consonants of **'t kofschip** (t, k, f, s, ch, p); otherwise **-d**.
+
+			| infinitive | stem | participle |
+			|---|---|---|
+			| werken | werk | gewerk**t** |
+			| wonen | woon | gewoon**d** |
+			| fietsen | fiets | gefiets**t** |
+			| leven | leef (from **v**!) | geleef**d** |
+			| reizen | reis (from **z**!) | gereis**d** |
+
+			Verbs starting with **be-, ge-, her-, ver-, ont-, er-** get no extra ge-: *betaald*, *vertelt → verteld*.
+
+			### Strong (irregular) verbs
+			Often end in **-en**: *gegeten, gedronken, gezien, geschreven, gelezen*. Learn them in the verb drill.
+
+			### Hebben or zijn?
+			Most verbs use **hebben**. **Zijn** is used for a change of place or state: *ik ben gegaan, gekomen, gebleven, geworden, gestorven*.
+			With movement verbs (lopen, fietsen, rijden) use **zijn** when a destination is given: *Ik ben naar huis gefietst* but *Ik heb veel gefietst*.
+
+			Separable verbs put ge- in the middle: *opgestaan*, *opgebeld*, *meegenomen*.
+		`,
+			words: `
+			gisteren | yesterday
+			vorige week | last week
+			vorig jaar | last year
+			al | already
+			nog niet | not yet
+			net | just
+			ooit | ever
+			gewerkt | worked
+			gegeten | eaten
+			gedronken | drunk
+			gezien | seen
+			gegaan | gone
+			gekomen | come (participle)
+			geweest | been
+			gehad | had
+			gedaan | done
+			gekocht | bought
+			gelezen | read (participle)
+			geschreven | written
+		`,
+			sentences: `
+			Wat heb je gisteren gedaan? | What did you do yesterday?
+			Ik heb de hele dag gewerkt. | I worked all day.
+			We zijn naar Rotterdam gegaan. | We went to Rotterdam.
+			Heb je die film al gezien? | Have you seen that film yet?
+			Ik ben nog nooit in België geweest. | I have never been to Belgium.
+			Ze heeft een nieuwe fiets gekocht. | She bought a new bike.
+			Hij is om zeven uur opgestaan. | He got up at seven.
+			Hebben jullie al gegeten? | Have you already eaten?
+		`,
+			drills: `
+			Ik heb hard ___. (werken) | gewerkt | gewerkd; gewerken; werkt | k is in 't kofschip: -t.
+			Wij hebben in Utrecht ___. (wonen) | gewoond | gewoont; gewonen; gewoon
+			Hij heeft veel ___. (reizen) | gereisd | gereist; gereizd; gereisen | The stem comes from reiz-: z is not in 't kofschip.
+			Ik ___ naar huis gegaan. | ben | heb; heeft; is
+			Zij ___ een boek gelezen. (she) | heeft | is; hebt; heb
+			Ik heb de rekening ___. (betalen) | betaald | gebetaald; betaalt; gebetaalt | Be- verbs get no ge-.
+			Ze zijn gisteren ___. (aankomen) | aangekomen | geaankomen; aankomen; aangekomt
+			We hebben pizza ___. (eten) | gegeten | geëet; geëten; geeten
+		`
+		}),
+		lesson({
+			id: 'nl-verleden',
+			title: 'Vroeger',
+			summary: 'The simple past: werkte, woonde, ging',
+			notes: `
+			The **simple past** (onvoltooid verleden tijd) is used in stories and for how things were.
+
+			### Regular verbs: stem + te(n) / de(n)
+			The same **'t kofschip** rule: stem ends in t, k, f, s, ch, p → **-te**, otherwise **-de**.
+
+			| | werken | wonen |
+			|---|---|---|
+			| ik / jij / hij | werk**te** | woon**de** |
+			| wij / jullie / zij | werk**ten** | woon**den** |
+
+			### Strong verbs change their vowel
+			| infinitive | singular | plural |
+			|---|---|---|
+			| zijn | was | waren |
+			| hebben | had | hadden |
+			| gaan | ging | gingen |
+			| komen | kwam | kwamen |
+			| zien | zag | zagen |
+			| eten | at | aten |
+			| drinken | dronk | dronken |
+			| lezen | las | lazen |
+			| schrijven | schreef | schreven |
+			| doen | deed | deden |
+
+			**Vroeger** (in the past, used to): *Vroeger woonde ik in Gent.* — I used to live in Ghent.
+		`,
+			words: `
+			vroeger | in the past; used to
+			toen | then; at that time
+			was | was
+			waren | were
+			had | had
+			ging | went
+			kwam | came
+			zag | saw
+			at | ate
+			dronk | drank
+			woonde | lived
+			werkte | worked
+			speelde | played
+			deed | did
+			het verhaal | the story
+			de jeugd | the youth; childhood
+		`,
+			sentences: `
+			Vroeger woonde ik in Gent. | I used to live in Ghent.
+			Toen ik klein was, speelde ik veel buiten. | When I was little, I played outside a lot.
+			Het was gisteren erg koud. | It was very cold yesterday.
+			We gingen elk jaar naar Frankrijk. | We went to France every year.
+			Hij kwam te laat op zijn werk. | He was late for work.
+			Ze dronken koffie en praatten lang. | They drank coffee and talked for a long time.
+			Ik had geen tijd. | I had no time.
+		`,
+			drills: `
+			Ik ___ vroeger in een fabriek. (werken) | werkte | werkde; werkten; werkt
+			Wij ___ in Leiden. (wonen) | woonden | woonde; woonten; wonden
+			Hij ___ elke dag naar school. (gaan) | ging | gaat; gingen; gaande
+			Jullie ___ te laat. (komen) | kwamen | kwam; komden; komten
+			Ik ___ een brief. (schrijven) | schreef | schrijfde; schreven; schrijfte
+			Zij ___ de hele dag. (dansen, she) | danste | dansde; dansten; dans
+			Het ___ een mooie dag. (zijn) | was | waren; is geweest; wees
+		`
+		}),
+		lesson({
+			id: 'nl-winkelen',
+			title: 'Winkelen',
+			summary: 'Shopping, clothes, plurals and diminutives',
+			notes: `
+			### Plurals
+			- Most nouns: **-en**: *boek → boeken*, *fiets → fietsen*.
+			- Nouns ending in unstressed **-el, -em, -en, -er, -je** and many loanwords: **-s**: *tafel → tafels*, *meisje → meisjes*.
+			- Nouns ending in a vowel: **'s**: *auto → auto's*, *foto → foto's*.
+
+			Spelling changes keep the vowel sound: *boom → bomen* (long), *bus → bussen* (short), *huis → huizen*, *brief → brieven*.
+			Some are irregular: *kind → kinderen*, *ei → eieren*, *stad → steden*.
+
+			### Diminutives (-je)
+			Dutch uses them constantly, also for things that aren't small (*een biertje*, *een momentje*). They are **always het**.
+			- Most words: **-je**: *huisje*, *boekje*.
+			- After a vowel or -l, -n, -r after long vowel: **-tje**: *autootje*, *stoeltje*, *treintje*.
+			- After -m: **-pje**: *boompje*.
+			- After a short vowel + l, m, n, r, ng: **-etje**: *balletje*, *ringetje*.
+		`,
+			words: `
+			kopen | to buy
+			betalen | to pay
+			kosten | to cost
+			de prijs | the price
+			de korting | the discount
+			de maat | the size
+			passen | to try on; to fit
+			de kassa | the checkout
+			pinnen | to pay by card
+			contant | cash
+			de broek | the trousers
+			het shirt | the T-shirt
+			de jas | the coat
+			de schoenen | the shoes
+			de jurk | the dress
+			de tas | the bag
+			te groot | too big
+			te klein | too small
+		`,
+			sentences: `
+			Hoeveel kost deze jas? | How much does this coat cost?
+			Mag ik dit passen? | May I try this on?
+			Heeft u dit in een grotere maat? | Do you have this in a bigger size?
+			De broek is te klein. | The trousers are too small.
+			Kan ik hier pinnen? | Can I pay by card here?
+			Ik betaal contant. | I'll pay cash.
+			Ik kijk alleen even rond. | I'm just looking around.
+			Wil je een tasje? | Would you like a bag?
+		`,
+			drills: `
+			één boek, twee ___ | boeken | boeks; boekken; boekes
+			één tafel, twee ___ | tafels | tafelen; tafellen; tafeles
+			één auto, twee ___ | auto's | autos; autoën; auten
+			één bus, twee ___ | bussen | busen; busses; buss
+			één huis, twee ___ | huizen | huisen; huises; huizes
+			een klein huis → een ___ | huisje | huistje; huizetje; huisetje
+			een kleine bal → een ___ | balletje | baltje; balje; balltje
+			___ boompje | het | de | Diminutives are always het.
+		`
+		}),
+		lesson({
+			id: 'nl-weer',
+			title: 'Het weer',
+			summary: 'Weather, seasons and talking about it',
+			notes: `
+			The Dutch talk about the weather a lot. Weather verbs use **het**: *het regent* (it's raining), *het sneeuwt*, *het waait* (it's windy), *het vriest*.
+
+			### Seasons
+			*de lente* (spring), *de zomer*, *de herfst* (autumn), *de winter*. **In** de zomer = in summer.
+
+			### Adverbs of degree
+			*heel* / *erg* (very), *best* (quite), *een beetje* (a bit), *te* (too), *veel te* (far too).
+
+			A famous expression: **Het regent pijpenstelen** — it's raining cats and dogs (literally "pipe stems").
+		`,
+			words: `
+			het weer | the weather
+			de zon | the sun
+			de regen | the rain
+			de wind | the wind
+			de sneeuw | the snow
+			de wolk | the cloud
+			regenen | to rain
+			waaien | to blow (wind)
+			warm | warm
+			koud | cold
+			nat | wet
+			droog | dry
+			bewolkt | cloudy
+			de lente | spring
+			de zomer | summer
+			de herfst | autumn
+			de winter | winter
+			de paraplu | the umbrella
+		`,
+			sentences: `
+			Wat voor weer is het? | What's the weather like?
+			Het regent weer. | It's raining again.
+			Het waait hard vandaag. | It's very windy today.
+			Morgen wordt het zonnig. | Tomorrow it will be sunny.
+			In de winter is het koud. | It's cold in winter.
+			Het is een beetje bewolkt. | It's a bit cloudy.
+			Neem een paraplu mee! | Take an umbrella!
+		`,
+			drills: `
+			___ regent. | Het | Er; De; Hij
+			It's windy: het ___ | waait | windt; blaast; wind
+			In de ___ vallen de bladeren. (autumn) | herfst | lente; zomer; winter
+			Het is ___ koud. (far too) | veel te | te veel; heel te; zeer te
+		`
+		}),
+		lesson({
+			id: 'nl-gezondheid',
+			title: 'Bij de dokter',
+			summary: 'Body, health and modal verbs',
+			notes: `
+			### Modal verbs
+			| | kunnen | willen | mogen | moeten |
+			|---|---|---|---|---|
+			| ik | kan | wil | mag | moet |
+			| jij | kunt / kan | wilt / wil | mag | moet |
+			| hij | kan | wil | mag | moet |
+			| wij | kunnen | willen | mogen | moeten |
+
+			The second verb goes **to the end as an infinitive**: *Ik moet naar de dokter **gaan**.* Often the *gaan* is dropped: *Ik moet naar de dokter.*
+
+			- **kunnen** — can, be able to
+			- **willen** — want
+			- **mogen** — may, be allowed to (also: to like a person — *ik mag hem wel*)
+			- **moeten** — must, have to. *Niet hoeven* = don't have to: *Je hoeft niet te komen.*
+
+			**Pijn** (pain): *Ik heb hoofdpijn, buikpijn, keelpijn.* — or *Mijn hoofd doet pijn.*
+		`,
+			words: `
+			het hoofd | the head
+			de buik | the belly
+			de keel | the throat
+			de rug | the back
+			de arm | the arm
+			het been | the leg
+			de voet | the foot
+			de hand | the hand
+			het oog | the eye
+			de pijn | the pain
+			ziek | ill
+			gezond | healthy
+			de huisarts | the GP
+			de apotheek | the pharmacy
+			het medicijn | the medicine
+			de afspraak | the appointment
+			beter worden | to get better
+		`,
+			sentences: `
+			Ik heb hoofdpijn. | I have a headache.
+			Mijn rug doet pijn. | My back hurts.
+			Ik moet naar de huisarts. | I have to go to the doctor.
+			Kan ik een afspraak maken? | Can I make an appointment?
+			U mag niet roken. | You're not allowed to smoke.
+			Je hoeft niet te werken. | You don't have to work.
+			Wil je iets drinken? | Do you want something to drink?
+			Beterschap! | Get well soon!
+		`,
+			drills: `
+			Ik ___ niet komen, ik ben ziek. (kunnen) | kan | kun; kunt; kunnen
+			Hij ___ een glas water. (willen) | wil | wilt; willen; wilde
+			Wij ___ morgen vroeg opstaan. (moeten) | moeten | moet; moesten; moeten te
+			Je ___ niet te komen. (don't have to) | hoeft | moet; mag; kan | Niet hoeven + te = not have to.
+			Ik moet naar de dokter ___. | gaan | ga; gaat; te gaan | The infinitive goes to the end.
+			Mijn buik doet ___. | pijn | ziek; slecht; pijnlijk
+		`
+		}),
+		lesson({
+			id: 'nl-thuis',
+			title: 'Thuis',
+			summary: 'The house, furniture and prepositions of place',
+			notes: `
+			### Prepositions of place
+			| | |
+			|---|---|
+			| in | in |
+			| op | on (touching the surface) |
+			| aan | on (a wall), at (the table) |
+			| onder | under |
+			| boven | above |
+			| naast | next to |
+			| tussen | between |
+			| voor | in front of |
+			| achter | behind |
+			| bij | at, near |
+
+			Dutch often uses a position verb instead of "is": **staan** (upright), **liggen** (flat), **zitten** (inside something), **hangen**:
+			*Het boek ligt op tafel. De fles staat in de koelkast. Het geld zit in mijn tas. De lamp hangt boven de tafel.*
+		`,
+			words: `
+			het huis | the house
+			het appartement | the apartment
+			de kamer | the room
+			de woonkamer | the living room
+			de slaapkamer | the bedroom
+			de keuken | the kitchen
+			de badkamer | the bathroom
+			de wc | the toilet
+			de tuin | the garden
+			de trap | the stairs
+			de muur | the wall
+			de vloer | the floor
+			de bank | the couch
+			de kast | the cupboard
+			de koelkast | the fridge
+			het bed | the bed
+			het raam | the window
+			de deur | the door
+		`,
+			sentences: `
+			Het boek ligt op tafel. | The book is on the table.
+			De melk staat in de koelkast. | The milk is in the fridge.
+			De kat zit onder het bed. | The cat is under the bed.
+			Er hangt een foto aan de muur. | There's a photo on the wall.
+			De badkamer is boven. | The bathroom is upstairs.
+			De sleutels zitten in mijn jas. | The keys are in my coat.
+			De bank staat tussen de kast en het raam. | The couch is between the cupboard and the window.
+		`,
+			drills: `
+			De fles ___ op tafel. (upright) | staat | ligt; zit; hangt
+			De krant ___ op de bank. (flat) | ligt | staat; hangt; zit
+			Het schilderij hangt ___ de muur. | aan | op; in; bij
+			Het geld ___ in mijn portemonnee. | zit | ligt; staat; hangt | Zitten = inside something.
+			De kat slaapt ___ het bed. (under) | onder | boven; tussen; achter
+		`
+		}),
+		lesson({
+			id: 'nl-vergelijken',
+			title: 'Vergelijken',
+			summary: 'Comparatives and superlatives',
+			notes: `
+			| | comparative (-er) | superlative (-st) |
+			|---|---|---|
+			| groot | groter | grootst |
+			| klein | kleiner | kleinst |
+			| mooi | mooier | mooist |
+			| duur | **duurder** | duurst |
+			| goed | **beter** | **best** |
+			| veel | **meer** | **meest** |
+			| weinig | **minder** | **minst** |
+			| graag | **liever** | **liefst** |
+
+			Adjectives ending in **-r** add **-der**: *duurder, lekkerder, zwaarder*.
+			**Dan** = than: *Ik ben ouder dan jij.* **Net zo … als** = as … as: *Hij is net zo lang als ik.*
+			The superlative after the verb: *het grootst*: *Deze kamer is het grootst.* Before a noun: *de grootste kamer*.
+
+			**Graag** means "gladly": *Ik drink graag thee* (I like drinking tea), *liever* (prefer), *het liefst* (like most of all).
+		`,
+			words: `
+			groter | bigger
+			kleiner | smaller
+			beter | better
+			best | best
+			meer | more
+			minder | less
+			duurder | more expensive
+			liever | rather; prefer
+			dan | than
+			net zo … als | as … as
+			ouder | older
+			jonger | younger
+			sneller | faster
+			langzamer | slower
+		`,
+			sentences: `
+			Ik ben ouder dan mijn zus. | I am older than my sister.
+			Amsterdam is groter dan Utrecht. | Amsterdam is bigger than Utrecht.
+			Dit is de beste pizza van de stad. | This is the best pizza in town.
+			De trein is sneller dan de bus. | The train is faster than the bus.
+			Ik drink liever thee dan koffie. | I prefer tea to coffee.
+			Hij is net zo lang als ik. | He is as tall as me.
+			Wat vind je het leukst? | What do you like most?
+		`,
+			drills: `
+			Deze jas is ___ dan die. (duur) | duurder | duurer; meer duur; duurst | Adjectives in -r add -der.
+			Jouw idee is ___ dan mijn idee. (goed) | beter | goeder; best; meer goed
+			Ik drink ___ water dan jij. (veel) | meer | veeler; meest; veel
+			Dit is de ___ film van het jaar. (goed) | beste | betere; goedste; best
+			Hij is net zo oud ___ ik. | als | dan; zo; wie
+			Ik ben groter ___ jij. | dan | als; of; zo
+		`
+		})
+	]
+);

src/lib/language-learner/courses/nl/b1.ts

@@ -0,0 +1,411 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b1',
+	'B1',
+	'Intermediate',
+	'Complex sentences, opinions, work, travel and the many uses of "er".',
+	[
+		lesson({
+			id: 'nl-bijzin',
+			title: 'Omdat, dat, als',
+			summary: 'Subordinate clauses: the verb goes to the end',
+			notes: `
+			After a **subordinating conjunction** the conjugated verb moves **to the end** of the clause:
+
+			- *Ik blijf thuis.* → *Ik blijf thuis **omdat ik ziek ben**.*
+			- *Ik denk **dat hij morgen komt**.*
+			- *Bel me **als je tijd hebt**.*
+
+			Common subordinators: **omdat** (because), **dat** (that), **als** (if, when), **wanneer** (when), **terwijl** (while), **hoewel** (although), **voordat** (before), **nadat** (after), **zodat** (so that), **of** (whether), **totdat** (until), **sinds** (since).
+
+			With several verbs, they cluster at the end: *…omdat ik morgen moet **werken**.* / *…omdat ik gisteren heb **gewerkt**.*
+
+			If the subordinate clause comes **first**, the main clause starts with its verb (verb-second rule):
+			*Als het regent, **blijf** ik thuis.*
+		`,
+			words: `
+			omdat | because
+			dat | that
+			als | if; when
+			terwijl | while
+			hoewel | although
+			voordat | before
+			nadat | after
+			zodat | so that
+			of | whether; or
+			totdat | until
+			sinds | since
+			zodra | as soon as
+		`,
+			sentences: `
+			Ik blijf thuis omdat ik ziek ben. | I'm staying home because I'm ill.
+			Ik denk dat hij morgen komt. | I think he's coming tomorrow.
+			Bel me als je tijd hebt. | Call me if you have time.
+			Als het regent, blijf ik thuis. | If it rains, I'll stay home.
+			Hij luistert naar muziek terwijl hij werkt. | He listens to music while he works.
+			Weet jij of de winkel open is? | Do you know whether the shop is open?
+			Hoewel het koud was, gingen we zwemmen. | Although it was cold, we went swimming.
+			Ik was mijn handen voordat ik kook. | I wash my hands before I cook.
+		`,
+			drills: `
+			Ik ga niet, omdat ik geen tijd ___. | heb | hebben; had gehad; heeft
+			Ik denk dat ___. | hij gelijk heeft | heeft hij gelijk; hij heeft gelijk; gelijk hij heeft
+			Als je honger hebt, ___ er brood. | is | er is; zijn; het is | After a subordinate clause, the main verb comes first.
+			Ik weet niet ___ hij komt. (whether) | of | dat; als; wanneer
+			Ze zegt dat ze morgen ___ ___. | moet werken | werken moet; werkt moet; moet werkt
+			___ hij rijk is, is hij niet gelukkig. | Hoewel | Omdat; Zodat; Terwijl
+		`
+		}),
+		lesson({
+			id: 'nl-want',
+			title: 'Want, maar, dus',
+			summary: 'Coordinating conjunctions and linking ideas',
+			notes: `
+			Some conjunctions **don't** change word order: **en** (and), **maar** (but), **of** (or), **want** (because), **dus** (so).
+
+			### want vs omdat
+			Both mean "because", but:
+			- *Ik blijf thuis, **want** ik **ben** ziek.* — normal word order
+			- *Ik blijf thuis, **omdat** ik ziek **ben**.* — verb to the end
+
+			**Want** can never start a sentence. **Omdat** can: *Omdat ik ziek ben, blijf ik thuis.*
+
+			### dus
+			*Dus* can be followed by normal order or inversion:
+			*Het regent, dus ik neem de bus.* / *Het regent, dus neem ik de bus.* Both are fine.
+
+			### Adverbial linkers (cause inversion)
+			**daarom** (that's why), **toch** (still, anyway), **daarna** (after that), **bovendien** (moreover), **anders** (otherwise):
+			*Ik was moe. **Daarom ging** ik vroeg naar bed.*
+		`,
+			words: `
+			want | because (no inversion)
+			maar | but
+			dus | so
+			daarom | that's why
+			toch | still; anyway
+			bovendien | moreover
+			anders | otherwise
+			eigenlijk | actually
+			namelijk | namely; you see
+			ook | also; too
+			niet alleen … maar ook | not only … but also
+		`,
+			sentences: `
+			Ik blijf thuis, want ik ben moe. | I'm staying home because I'm tired.
+			Het regent, dus ik neem de bus. | It's raining, so I'm taking the bus.
+			Ik was moe. Daarom ging ik vroeg naar bed. | I was tired. That's why I went to bed early.
+			Het was duur, maar ik heb het toch gekocht. | It was expensive, but I bought it anyway.
+			Haast je, anders mis je de trein. | Hurry, otherwise you'll miss the train.
+			Ik kan niet komen, ik moet namelijk werken. | I can't come; I have to work, you see.
+			Eigenlijk wil ik liever thuisblijven. | Actually I'd rather stay home.
+		`,
+			drills: `
+			Ik eet niets, want ___. | ik heb geen honger | ik geen honger heb; heb ik geen honger; geen honger ik heb
+			Ik eet niets, omdat ___. | ik geen honger heb | ik heb geen honger; heb ik geen honger; geen honger heb ik
+			Ik was ziek. Daarom ___ thuis. | bleef ik | ik bleef; bleef; ik ben gebleven thuis
+			Het was koud, ___ gingen we naar buiten. (anyway) | toch | want; omdat; daarom
+			___ ik moe ben, ga ik slapen. | Omdat | Want; Dus; Maar | Want can't start a sentence.
+		`
+		}),
+		lesson({
+			id: 'nl-werk',
+			title: 'Werk en studie',
+			summary: 'Jobs, applying, the office',
+			notes: `
+			### Talking about your work
+			- *Wat doe je voor werk?* / *Wat voor werk doe je?* — What do you do?
+			- *Ik werk **bij** een bank.* — I work **at** a bank (company).
+			- *Ik werk **als** programmeur.* — I work **as** a programmer.
+			- *Ik ben programmeur.* — no article before professions!
+
+			Dutch work culture is direct and fairly informal: colleagues use **je/jij**, and meetings (*overleggen*) are frequent.
+			A **ZZP'er** (zelfstandige zonder personeel) is a freelancer.
+		`,
+			words: `
+			de baan | the job
+			het werk | the work
+			de collega | the colleague
+			de baas | the boss
+			de werkgever | the employer
+			de werknemer | the employee
+			het salaris | the salary
+			solliciteren | to apply (for a job)
+			de sollicitatie | the application
+			het sollicitatiegesprek | the job interview
+			het cv | the CV
+			de vergadering | the meeting
+			het overleg | the consultation; the meeting
+			de opleiding | the education; the training
+			de stage | the internship
+			ervaring | experience
+			fulltime | full-time
+			parttime | part-time
+			ontslaan | to fire
+		`,
+			sentences: `
+			Wat doe je voor werk? | What do you do for a living?
+			Ik werk als verpleegkundige. | I work as a nurse.
+			Ze werkt bij een groot bedrijf. | She works at a large company.
+			Ik heb morgen een sollicitatiegesprek. | I have a job interview tomorrow.
+			Hij heeft veel ervaring met klanten. | He has a lot of experience with customers.
+			De vergadering duurt tot drie uur. | The meeting lasts until three o'clock.
+			Ik werk vier dagen per week. | I work four days a week.
+			Ze is vorig jaar ontslagen. | She was fired last year.
+		`,
+			drills: `
+			Ik werk ___ een ziekenhuis. | bij | als; in de; voor een
+			Hij werkt ___ leraar. | als | bij; voor; zoals
+			Ik wil ___ voor die baan. (apply) | solliciteren | applyen; aanmelden; vragen
+		`
+		}),
+		lesson({
+			id: 'nl-betrekkelijk',
+			title: 'Die en dat',
+			summary: 'Relative clauses',
+			notes: `
+			Relative pronouns connect a clause to a noun. The verb goes to the end:
+
+			- **die** for **de-words** and all **plurals**: *de man **die** daar staat*, *de boeken **die** ik lees*
+			- **dat** for **het-words** (singular): *het huis **dat** ik koop*
+
+			With a preposition, use **waar + preposition** for things: *de stoel **waarop** ik zit*, *de pen **waarmee** ik schrijf*.
+			For people use **preposition + wie**: *de vrouw **met wie** ik praat*.
+
+			**Wat** is used after *alles, iets, niets, het enige* and superlatives:
+			*Alles **wat** ik weet…*, *Het mooiste **wat** ik ken…*
+		`,
+			words: `
+			die | who; which; that (de-words)
+			dat | which; that (het-words)
+			wat | what; which (after alles, iets)
+			waarmee | with which
+			waarover | about which
+			waarop | on which
+			met wie | with whom
+			iemand | someone
+			iets | something
+			niets | nothing
+			alles | everything
+		`,
+			sentences: `
+			De man die daar staat, is mijn buurman. | The man standing there is my neighbour.
+			Het boek dat ik lees, is spannend. | The book I'm reading is exciting.
+			De mensen die hier wonen, zijn aardig. | The people who live here are nice.
+			Dat is de pen waarmee ik schrijf. | That's the pen I write with.
+			De vrouw met wie ik praat, is lerares. | The woman I'm talking to is a teacher.
+			Alles wat hij zegt, is waar. | Everything he says is true.
+			Is er iets wat ik kan doen? | Is there anything I can do?
+		`,
+			drills: `
+			de fiets ___ ik gekocht heb | die | dat; wat; wie
+			het huis ___ ik gekocht heb | dat | die; wat; wie
+			de kinderen ___ buiten spelen | die | dat; wat; wie | Plurals always take die.
+			alles ___ je ziet | wat | dat; die; wie
+			het mes ___ ik snijd (with which) | waarmee | met wat; met dat; met die
+			de collega ___ ik werk (with whom) | met wie | waarmee; met die; met wat
+		`
+		}),
+		lesson({
+			id: 'nl-toekomst',
+			title: 'De toekomst',
+			summary: 'Talking about the future: gaan, zullen, present',
+			notes: `
+			Dutch often uses the **present tense** with a time word for the future: *Morgen **werk** ik thuis.*
+
+			**Gaan + infinitive** — plans and predictions (like "going to"):
+			*Ik **ga** volgend jaar in Spanje **wonen**.* *Het **gaat** regenen.*
+
+			**Zullen + infinitive** — promises, formal predictions, suggestions:
+			| zullen | |
+			|---|---|
+			| ik zal | wij zullen |
+			| jij zult / zal | jullie zullen |
+			| hij zal | zij zullen |
+
+			- Promise: *Ik **zal** je helpen.*
+			- Suggestion: ***Zullen** we koffie drinken?* — Shall we have coffee?
+			- Probability: *Hij **zal** wel moe zijn.* — He's probably tired.
+		`,
+			words: `
+			volgend jaar | next year
+			volgende week | next week
+			straks | later; soon
+			binnenkort | soon
+			later | later
+			zullen | shall; will
+			van plan zijn | to plan to
+			hopen | to hope
+			verwachten | to expect
+			misschien | maybe
+			waarschijnlijk | probably
+			zeker | certainly
+		`,
+			sentences: `
+			Ik ga volgend jaar in Spanje wonen. | I'm going to live in Spain next year.
+			Het gaat regenen. | It's going to rain.
+			Ik zal je morgen helpen. | I'll help you tomorrow.
+			Zullen we een film kijken? | Shall we watch a film?
+			Hij zal wel moe zijn. | He's probably tired.
+			Ik ben van plan om te verhuizen. | I'm planning to move.
+			Misschien kom ik later. | Maybe I'll come later.
+			Ik hoop dat het morgen mooi weer is. | I hope the weather will be nice tomorrow.
+		`,
+			drills: `
+			___ we naar het strand gaan? (shall) | Zullen | Gaan; Willen; Worden
+			Ik ___ je morgen bellen. (promise) | zal | zul; zullen; wil
+			Het gaat morgen ___. (sneeuwen) | sneeuwen | sneeuwt; gesneeuwd; te sneeuwen
+			Ik ben van plan ___ te stoppen. | om | voor; te; dat
+		`
+		}),
+		lesson({
+			id: 'nl-er',
+			title: 'Het woordje "er"',
+			summary: 'The five uses of er',
+			notes: `
+			**Er** is one of the trickiest Dutch words. It has five main jobs:
+
+			1. **Existence** (there is/are): ***Er** is een probleem.*
+			2. **Place** (there), unstressed: *Ben je **er** al geweest?* — Have you been there yet?
+			3. **Quantity** (of them), with numbers: *Ik heb **er** twee.* — I have two (of them).
+			4. **With prepositions** (replaces *het* for things): *Ik denk **eraan**.* — I'm thinking about it. *Wat vind je **ervan**?*
+			5. **Passive without subject**: ***Er** wordt gedanst.* — There is dancing.
+
+			With prepositions *er* can be split: *Ik heb **er** niet **aan** gedacht.* — I didn't think of it.
+
+			Special forms: *met → ermee*, *tot → ertoe*.
+		`,
+			words: `
+			er | there; of them; it
+			eraan | about it; of it
+			ervan | of it; about it
+			ermee | with it
+			erover | about it
+			erop | on it
+			erin | in it
+			erbij | with it; included
+			denken aan | to think about
+			houden van | to love; to like
+			praten over | to talk about
+		`,
+			sentences: `
+			Er is een probleem. | There's a problem.
+			Ben je er al geweest? | Have you been there yet?
+			Hoeveel katten heb je? Ik heb er twee. | How many cats do you have? I have two.
+			Wat vind je ervan? | What do you think of it?
+			Ik heb er niet aan gedacht. | I didn't think of it.
+			Ik ben er klaar mee. | I'm done with it.
+			We moeten erover praten. | We need to talk about it.
+			Er wordt veel gefietst in Nederland. | People cycle a lot in the Netherlands.
+		`,
+			drills: `
+			Heb je appels? Ja, ik heb ___ drie. | er | ze; het; die | Quantity: er + number.
+			Ik denk ___. (about it) | eraan | aan het; erover het; daar | Er replaces "het" after a preposition.
+			Wat vind je ___? (of it) | ervan | van het; daarvan het; het van
+			Hij speelt ___. (with it) | ermee | met het; ermet; met er
+			___ wordt gebeld. | Er | Het; Men; Daar
+		`
+		}),
+		lesson({
+			id: 'nl-mening',
+			title: 'Mijn mening',
+			summary: 'Giving opinions, agreeing and disagreeing',
+			notes: `
+			The Dutch are known for being direct. Useful ways to give your opinion:
+
+			- **Ik vind** + opinion: *Ik vind het een goed idee.* (*vinden* = to think/find, for opinions)
+			- **Ik denk dat** … (think, for expectations): *Ik denk dat het gaat regenen.*
+			- **Volgens mij** … — in my opinion: *Volgens mij heeft hij gelijk.*
+			- **Het eens zijn met** — to agree with: *Ik ben het met je eens.* / *Ik ben het niet met je eens.*
+			- **Gelijk hebben** — to be right: *Je hebt gelijk.*
+
+			Don't confuse **vinden** (opinion) with **denken** (believe, expect):
+			*Ik vind die film saai* (opinion), *Ik denk dat de film om acht uur begint* (belief).
+		`,
+			words: `
+			de mening | the opinion
+			vinden | to find; to think (opinion)
+			denken | to think
+			volgens mij | in my opinion
+			het eens zijn | to agree
+			gelijk hebben | to be right
+			het idee | the idea
+			het voordeel | the advantage
+			het nadeel | the disadvantage
+			belangrijk | important
+			eerlijk | honest; fair
+			natuurlijk | of course; natural
+			inderdaad | indeed
+			juist | exactly; correct
+		`,
+			sentences: `
+			Wat vind jij ervan? | What do you think of it?
+			Ik vind het een goed idee. | I think it's a good idea.
+			Volgens mij heeft hij gelijk. | In my opinion, he's right.
+			Ik ben het helemaal met je eens. | I completely agree with you.
+			Daar ben ik het niet mee eens. | I don't agree with that.
+			Het voordeel is dat het goedkoop is. | The advantage is that it's cheap.
+			Eerlijk gezegd vind ik het saai. | To be honest, I find it boring.
+		`,
+			drills: `
+			Ik ___ die film heel mooi. (opinion) | vind | denk; meen; geloof
+			Ik ___ dat de trein om acht uur gaat. (expectation) | denk | vind; zie; weet niet
+			Ik ben het ___ je eens. | met | aan; voor; bij
+			Je hebt ___. (you're right) | gelijk | recht; goed; juist
+			___ mij is dat niet waar. | Volgens | Voor; Van; Door
+		`
+		}),
+		lesson({
+			id: 'nl-reizen',
+			title: 'Op reis',
+			summary: 'Travel, public transport and the OV',
+			notes: `
+			Public transport is **het openbaar vervoer (OV)**. You check in and out with a bank card or **OV-chipkaart**: *inchecken* and *uitchecken*.
+
+			Useful verbs:
+			- **overstappen** — to change (trains): *U moet in Utrecht overstappen.*
+			- **vertraging hebben** — to be delayed: *De trein heeft tien minuten vertraging.*
+			- **missen** — to miss: *Ik heb de trein gemist.*
+			- **halen** — to catch (make it): *Ik haal de trein niet!*
+
+			Announcements: *"De trein naar Amsterdam Centraal vertrekt van spoor vijf."*
+		`,
+			words: `
+			de reis | the trip
+			reizen | to travel
+			het openbaar vervoer | public transport
+			de trein | the train
+			het spoor | the track; the platform
+			het perron | the platform
+			de vertraging | the delay
+			overstappen | to change (trains)
+			inchecken | to check in
+			uitchecken | to check out
+			het kaartje | the ticket
+			de koffer | the suitcase
+			het vliegveld | the airport
+			de vlucht | the flight
+			het hotel | the hotel
+			boeken | to book
+			de vakantie | the holiday
+			het buitenland | abroad
+		`,
+			sentences: `
+			De trein heeft twintig minuten vertraging. | The train is twenty minutes late.
+			U moet in Utrecht overstappen. | You have to change in Utrecht.
+			Van welk spoor vertrekt de trein? | Which platform does the train leave from?
+			Vergeet niet uit te checken! | Don't forget to check out!
+			Ik heb de laatste bus gemist. | I missed the last bus.
+			We gaan deze zomer naar het buitenland. | We're going abroad this summer.
+			Ik heb een hotel geboekt. | I booked a hotel.
+		`,
+			drills: `
+			De trein heeft ___. (is delayed) | vertraging | laat; te laat; vertraagd
+			U moet in Amersfoort ___. (change) | overstappen | veranderen; wisselen; omstappen
+			Ik heb de trein ___. (missed) | gemist | gemissd; gemisst; mist
+			We gaan naar het ___. (abroad) | buitenland | uitland; overzee; buitenlands
+		`
+		})
+	]
+);

src/lib/language-learner/courses/nl/b2.ts

@@ -0,0 +1,370 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'b2',
+	'B2',
+	'Upper intermediate',
+	'Passive voice, conditionals, particles that give Dutch its flavour, and idioms.',
+	[
+		lesson({
+			id: 'nl-passief',
+			title: 'De lijdende vorm',
+			summary: 'The passive: worden and zijn',
+			notes: `
+			The passive uses **worden** + participle (present / simple past) and **zijn** + participle (perfect):
+
+			| tense | example |
+			|---|---|
+			| present | Het huis **wordt** gebouwd. |
+			| simple past | Het huis **werd** gebouwd. |
+			| perfect | Het huis **is** gebouwd. (not *is geworden*) |
+			| future | Het huis **zal** gebouwd **worden**. |
+
+			The agent is introduced with **door**: *Het boek is **door** Mulisch geschreven.*
+
+			Watch out: *Het huis is gebouwd* means "has been built" (perfect passive), not "is built" as a state.
+
+			**Er**-passive without a subject: *Er wordt hier niet gerookt.* — No smoking here.
+		`,
+			words: `
+			worden | to become; to be (passive)
+			door | by (agent)
+			bouwen | to build
+			uitvinden | to invent
+			ontdekken | to discover
+			vertalen | to translate
+			verkopen | to sell
+			sluiten | to close
+			stelen | to steal
+			repareren | to repair
+			gesloten | closed
+			gestolen | stolen
+			verboden | forbidden
+		`,
+			sentences: `
+			Het huis wordt gebouwd. | The house is being built.
+			Mijn fiets is gestolen. | My bike has been stolen.
+			Het boek werd in 1960 geschreven. | The book was written in 1960.
+			Dit boek is door Mulisch geschreven. | This book was written by Mulisch.
+			Er wordt hier niet gerookt. | There is no smoking here.
+			De winkel wordt om zes uur gesloten. | The shop is closed at six.
+			Het probleem zal morgen opgelost worden. | The problem will be solved tomorrow.
+		`,
+			drills: `
+			De brief ___ morgen verstuurd. | wordt | is; heeft; zal | Present passive: worden.
+			Mijn portemonnee ___ gisteren gestolen. | is | wordt; heeft; werd geworden | Perfect passive uses zijn, not "is geworden".
+			Het schilderij is ___ Rembrandt gemaakt. | door | van; bij; met
+			___ wordt veel gelachen. | Er | Het; Men; Daar
+			De film ___ in 1995 gemaakt. | werd | wordt; worden; was geworden
+		`
+		}),
+		lesson({
+			id: 'nl-zou',
+			title: 'Als ik rijk was…',
+			summary: 'Conditionals with zou and zouden',
+			notes: `
+			### Hypothetical present
+			**Als** + simple past, main clause with **zou(den)** + infinitive:
+			*Als ik rijk **was**, **zou** ik een boot **kopen**.* — If I were rich, I'd buy a boat.
+
+			### Hypothetical past
+			**Als** + *had/was* + participle, main clause with **zou hebben/zijn** + participle — or simply the pluperfect in both:
+			*Als ik het **had geweten**, **zou** ik **zijn gekomen**.*
+			*Als ik het **had geweten**, **was** ik **gekomen**.* (more common in speech)
+
+			### Politeness
+			**Zou** makes requests polite: ***Zou** je het raam dicht willen doen?*
+			**Zouden** also reports rumours: *De minister **zou** ontslag nemen.* — The minister is said to resign.
+		`,
+			words: `
+			zou | would (singular)
+			zouden | would (plural)
+			als | if
+			rijk | rich
+			graag willen | would like
+			in jouw plaats | in your place
+			stel dat | suppose that
+			anders | otherwise
+			eventueel | possibly; if need be
+			het geval | the case
+			in dat geval | in that case
+		`,
+			sentences: `
+			Als ik rijk was, zou ik een boot kopen. | If I were rich, I'd buy a boat.
+			Ik zou graag een kamer willen reserveren. | I would like to reserve a room.
+			Zou je me kunnen helpen? | Could you help me?
+			Als ik jou was, zou ik het doen. | If I were you, I'd do it.
+			Als ik het had geweten, was ik gekomen. | If I'd known, I would have come.
+			Stel dat je de loterij wint. | Suppose you win the lottery.
+			Wat zou jij doen? | What would you do?
+		`,
+			drills: `
+			Als ik tijd ___, zou ik je helpen. | had | heb; zou hebben; hebt
+			Als ik jou ___, zou ik stoppen. | was | ben; zou zijn; bent
+			Wij ___ graag willen komen. | zouden | zou; zullen; zul
+			Als ik het had geweten, ___ ik gebleven. | was | had; ben; werd | Blijven takes zijn.
+			___ u iets harder kunnen praten? | Zou | Zal; Wil; Kan
+		`
+		}),
+		lesson({
+			id: 'nl-voornaamwoordelijk',
+			title: 'Daarover, waarmee',
+			summary: 'Pronominal adverbs and verbs with fixed prepositions',
+			notes: `
+			Many Dutch verbs have a **fixed preposition**:
+
+			| | |
+			|---|---|
+			| wachten **op** | to wait for |
+			| denken **aan** | to think of/about |
+			| houden **van** | to love |
+			| zorgen **voor** | to take care of |
+			| praten **over** | to talk about |
+			| geïnteresseerd zijn **in** | to be interested in |
+			| bang zijn **voor** | to be afraid of |
+			| trots zijn **op** | to be proud of |
+			| boos zijn **op** | to be angry with |
+			| zin hebben **in** | to feel like |
+
+			For **things**, the preposition + pronoun becomes one word: **er-, daar-, waar-** + preposition:
+			- *Ik wacht **erop**.* — I'm waiting for it.
+			- ***Daar** heb ik geen zin **in**.* — I don't feel like that.
+			- ***Waar** denk je **aan**?* — What are you thinking about?
+
+			For people, keep preposition + pronoun: *Ik wacht **op hem**.*
+		`,
+			words: `
+			wachten op | to wait for
+			denken aan | to think of
+			houden van | to love
+			zorgen voor | to take care of
+			geïnteresseerd zijn in | to be interested in
+			bang zijn voor | to be afraid of
+			trots zijn op | to be proud of
+			boos zijn op | to be angry with
+			zin hebben in | to feel like
+			genieten van | to enjoy
+			afhangen van | to depend on
+			twijfelen aan | to doubt
+		`,
+			sentences: `
+			Waar wacht je op? | What are you waiting for?
+			Ik heb geen zin in werken. | I don't feel like working.
+			Daar heb ik nooit aan gedacht. | I never thought of that.
+			Ze is erg trots op haar dochter. | She is very proud of her daughter.
+			Het hangt ervan af. | It depends.
+			Waar ben je bang voor? | What are you afraid of?
+			Ik geniet ervan. | I'm enjoying it.
+			Hij zorgt voor zijn moeder. | He takes care of his mother.
+		`,
+			drills: `
+			Ik wacht ___ de bus. | op | voor; naar; aan
+			Ze houdt ___ chocola. | van | op; met; aan
+			Hij is geïnteresseerd ___ kunst. | in | voor; aan; op
+			Ik denk ___. (of it) | eraan | aan het; eraf; erop
+			___ ben je boos op? (what) | Waar | Wat; Wie; Waarop
+			Heb je ___ in pizza? | zin | lust; honger; wil
+		`
+		}),
+		lesson({
+			id: 'nl-partikels',
+			title: 'Toch, even, maar, wel',
+			summary: 'Modal particles: the words that make Dutch sound natural',
+			notes: `
+			Short words like **even, maar, toch, wel, eens, hoor, nou, gewoon** don't change the facts but change the **tone**. Natives use them constantly.
+
+			| particle | effect | example |
+			|---|---|---|
+			| **even** | "just quickly", softens a request | *Kun je **even** helpen?* |
+			| **maar** | encouraging, "go ahead" | *Kom **maar** binnen.* |
+			| **eens** | friendly suggestion | *Kijk **eens**!* |
+			| **toch** | "surely, right?", seeking agreement | *Je komt **toch**?* |
+			| **wel** | contrast, "actually", reassurance | *Het komt **wel** goed.* |
+			| **hoor** | reassurance, softens a statement | *Dat is goed, **hoor**.* |
+			| **nou** | impatience or emphasis | ***Nou**, en?* |
+			| **gewoon** | "simply, just" | *Doe **gewoon** normaal.* |
+
+			They're often stacked: *Kom **toch maar eens** langs!* — Do come by sometime!
+		`,
+			words: `
+			even | just (for a moment)
+			maar | just; go ahead
+			toch | surely; still; after all
+			wel | actually; indeed (contrast)
+			eens | once; sometime
+			hoor | you know (reassurance)
+			nou | well; now
+			gewoon | just; simply; normal
+			zeker | certainly; surely
+			heus | really; truly
+			nogal | rather; quite
+			best | quite; fine
+		`,
+			sentences: `
+			Kun je even helpen? | Could you just help for a moment?
+			Kom maar binnen. | Come on in.
+			Je komt toch ook? | You're coming too, right?
+			Het komt wel goed. | It'll be fine.
+			Dat is niet erg, hoor. | That's okay, don't worry.
+			Doe gewoon normaal. | Just act normal.
+			Kom eens langs! | Come by some time!
+			Het is nogal duur. | It's rather expensive.
+		`,
+			drills: `
+			Kom ___ binnen, de deur is open. (encouraging) | maar | even; toch; nou
+			Kun je ___ het zout geven? (quick request) | even | maar; toch; nou
+			Ik ben niet rijk, maar ik ben ___ gelukkig. (contrast) | wel | toch; even; hoor
+			Je weet het ___ ook? (surely) | toch | wel; maar; eens
+			Maak je geen zorgen, het is goed, ___. | hoor | toch; even; wel
+		`
+		}),
+		lesson({
+			id: 'nl-te',
+			title: 'Om te',
+			summary: 'Infinitive constructions with te and om … te',
+			notes: `
+			### te + infinitive
+			After many verbs the second verb takes **te**: *Ik probeer **te** slapen. Het begint **te** regenen. Hij vergeet **te** bellen.*
+
+			No *te* after modal verbs (*kunnen, moeten, willen, mogen, zullen*) or *gaan, komen, blijven, laten, zien, horen*:
+			*Ik kan zwemmen. Ik ga slapen.*
+
+			### om … te — purpose, "in order to"
+			*Ik ga naar de winkel **om** brood **te** kopen.* — I'm going to the shop to buy bread.
+
+			**Om te** is also used after adjectives and nouns: *Het is leuk **om te** doen. Ik heb geen tijd **om te** koken.*
+
+			### zitten/staan/liggen + te — ongoing action
+			*Hij **zit te** lezen.* — He's (sitting) reading. *Ze **staat te** wachten.*
+			Also: **aan het** + infinitive: *Ik ben **aan het** koken.* — I'm cooking.
+		`,
+			words: `
+			proberen | to try
+			beginnen | to begin
+			vergeten | to forget
+			beloven | to promise
+			besluiten | to decide
+			weigeren | to refuse
+			hoeven | to need to (with niet)
+			durven | to dare
+			aan het … zijn | to be busy …ing
+			om … te | in order to
+			zonder … te | without …ing
+			in plaats van … te | instead of …ing
+		`,
+			sentences: `
+			Ik probeer te slapen. | I'm trying to sleep.
+			Het begint te regenen. | It's starting to rain.
+			Ik ga naar de winkel om brood te kopen. | I'm going to the shop to buy bread.
+			Ik heb geen tijd om te koken. | I don't have time to cook.
+			Hij zit de hele dag te gamen. | He sits gaming all day.
+			We zijn aan het eten. | We're eating.
+			Hij vertrok zonder iets te zeggen. | He left without saying anything.
+			Ze besloot om te verhuizen. | She decided to move.
+		`,
+			drills: `
+			Ik kan goed ___. (zwemmen) | zwemmen | te zwemmen; om te zwemmen; zwem | No te after modal verbs.
+			Hij vergat ___. (bellen) | te bellen | bellen; om bellen; gebeld
+			Ik spaar geld ___ een auto ___ kopen. | om … te | voor … te; om … –; te … om
+			Ze ___ te wachten op de bus. (standing) | staat | zit; ligt; is
+			Ik ben ___ koken. | aan het | om te; bezig; te
+		`
+		}),
+		lesson({
+			id: 'nl-nieuws',
+			title: 'Het nieuws',
+			summary: 'Society, politics and news vocabulary',
+			notes: `
+			The Netherlands is a **constitutional monarchy** with a parliamentary democracy.
+			- **De Tweede Kamer** — House of Representatives (150 seats), the most important chamber.
+			- **Het kabinet** — the cabinet; **de minister-president** — the prime minister.
+			- Governments are always **coalitions** (*een coalitie*) of several parties, formed after long negotiations (*de formatie*).
+
+			Reading tip: news headlines drop articles and verbs: *"Kabinet valt na ruzie over asiel"* — The cabinet falls after a row over asylum.
+		`,
+			words: `
+			de regering | the government
+			het kabinet | the cabinet
+			de minister | the minister
+			de verkiezingen | the elections
+			stemmen | to vote
+			de partij | the (political) party
+			de coalitie | the coalition
+			de wet | the law
+			de belasting | the tax
+			de economie | the economy
+			de werkloosheid | unemployment
+			het onderzoek | the research; the investigation
+			volgens | according to
+			de maatschappij | society
+			het milieu | the environment
+			de klimaatverandering | climate change
+			de woningnood | the housing shortage
+			het protest | the protest
+		`,
+			sentences: `
+			Er zijn volgend jaar verkiezingen. | There are elections next year.
+			Op welke partij ga je stemmen? | Which party are you going to vote for?
+			De regering wil de belasting verhogen. | The government wants to raise taxes.
+			Volgens onderzoek fietsen Nederlanders steeds meer. | According to research, Dutch people are cycling more and more.
+			De woningnood is een groot probleem. | The housing shortage is a big problem.
+			Het kabinet is gevallen. | The cabinet has fallen.
+			De werkloosheid daalt. | Unemployment is falling.
+		`,
+			drills: `
+			Ik ga ___ op een kleine partij. (vote) | stemmen | kiezen; voten; stemmen voor
+			___ de krant wordt het morgen warm. | Volgens | Door; Van; Na
+			De ___ is gevallen. (cabinet) | kabinet | kast; kabinetje; regeer
+		`
+		}),
+		lesson({
+			id: 'nl-uitdrukkingen',
+			title: 'Uitdrukkingen',
+			summary: 'Everyday Dutch idioms',
+			notes: `
+			Dutch idioms are vivid, often about food, animals and the weather. Don't translate them literally!
+
+			| idiom | literally | meaning |
+			|---|---|---|
+			| Het regent pijpenstelen. | It's raining pipe stems. | It's pouring. |
+			| Iemand in de maling nemen | to take someone in the grinder | to pull someone's leg |
+			| Met de deur in huis vallen | to fall into the house with the door | to get straight to the point |
+			| Nu komt de aap uit de mouw. | Now the monkey comes out of the sleeve. | Now the truth comes out. |
+			| Dat is een koud kunstje. | That's a cold trick. | That's a piece of cake. |
+			| Tot in de puntjes | to the little points | down to the last detail |
+			| Een appeltje te schillen hebben | to have an apple to peel | to have a bone to pick |
+			| Zo gek als een deur | as crazy as a door | completely mad |
+			| Voor een appel en een ei | for an apple and an egg | for next to nothing |
+			| De kat uit de boom kijken | to watch the cat out of the tree | to wait and see |
+		`,
+			words: `
+			het regent pijpenstelen | it's raining cats and dogs
+			iemand in de maling nemen | to pull someone's leg
+			met de deur in huis vallen | to get straight to the point
+			nu komt de aap uit de mouw | now the truth comes out
+			een koud kunstje | a piece of cake
+			tot in de puntjes | down to the last detail
+			een appeltje te schillen hebben | to have a bone to pick
+			voor een appel en een ei | for next to nothing
+			de kat uit de boom kijken | to wait and see
+			zo gek als een deur | completely mad
+			ik heb er een hard hoofd in | I have my doubts about it
+			dat zit wel snor | that'll be fine
+		`,
+			sentences: `
+			Ik val maar met de deur in huis: ik stop. | I'll get straight to the point: I'm quitting.
+			Je neemt me in de maling! | You're pulling my leg!
+			Ik heb die fiets voor een appel en een ei gekocht. | I bought that bike for next to nothing.
+			Ik heb nog een appeltje met je te schillen. | I have a bone to pick with you.
+			We kijken eerst de kat uit de boom. | We'll wait and see first.
+			Alles was tot in de puntjes geregeld. | Everything was organised down to the last detail.
+		`,
+			drills: `
+			It's pouring: het regent ___ | pijpenstelen | katten en honden; emmers; bakstenen
+			To pull someone's leg: iemand in de ___ nemen | maling | molen; boot; war
+			For next to nothing: voor een appel en een ___ | ei | peer; banaan; brood
+			Now the truth comes out: nu komt de ___ uit de mouw | aap | kat; muis; hond
+		`
+		})
+	]
+);

src/lib/language-learner/courses/nl/c1.ts

@@ -0,0 +1,318 @@
+import { lesson, level } from '../../course';
+
+export default level(
+	'c1',
+	'C1',
+	'Advanced',
+	'Formal register, verb clusters, false friends, nuance and proverbs.',
+	[
+		lesson({
+			id: 'nl-formeel',
+			title: 'Formeel schrijven',
+			summary: 'Formal register and written connectors',
+			notes: `
+			Formal written Dutch (*ambtelijke taal* when overdone) prefers longer connectors:
+
+			| everyday | formal | meaning |
+			|---|---|---|
+			| maar | echter | however |
+			| omdat | aangezien | since, as |
+			| dus | derhalve / daarom | therefore |
+			| toch | desondanks / desalniettemin | nevertheless |
+			| over | betreffende / inzake | regarding |
+			| als | indien | if |
+			| krijgen | ontvangen | to receive |
+			| sturen | toezenden | to send |
+
+			**Echter** is not used at the start of a sentence in good style: *Het plan is goed. Het is **echter** duur.*
+
+			Formal letters: *Geachte heer/mevrouw …* — *Met vriendelijke groet*.
+			Emails between colleagues: *Beste Anna,* … *Groet,* / *Groetjes* (informal).
+		`,
+			words: `
+			echter | however
+			aangezien | since; given that
+			derhalve | therefore
+			desondanks | nevertheless
+			indien | if (formal)
+			betreffende | regarding
+			ten aanzien van | with regard to
+			naar aanleiding van | following; in response to
+			in verband met | in connection with; due to
+			met betrekking tot | with respect to
+			hoogachtend | yours faithfully
+			geachte | dear (formal)
+			bijgevoegd | attached
+			in behandeling nemen | to process; to handle
+		`,
+			sentences: `
+			Geachte mevrouw De Vries, | Dear Mrs De Vries,
+			Naar aanleiding van uw brief laat ik u het volgende weten. | In response to your letter, I would like to inform you of the following.
+			Het voorstel is interessant; het is echter te duur. | The proposal is interesting; however, it is too expensive.
+			Aangezien de termijn verlopen is, kunnen wij uw aanvraag niet in behandeling nemen. | Since the deadline has passed, we cannot process your application.
+			Indien u vragen heeft, kunt u contact met ons opnemen. | Should you have any questions, you can contact us.
+			In verband met ziekte is de winkel gesloten. | Due to illness, the shop is closed.
+			Bijgevoegd vindt u mijn cv. | Please find my CV attached.
+		`,
+			drills: `
+			Formal "als": ___ u niet tevreden bent, … | Indien | Aangezien; Echter; Derhalve
+			Formal "omdat": ___ het regent, gaat het feest niet door. | Aangezien | Echter; Indien; Desondanks
+			Het was duur. Hij kocht het ___. (nevertheless) | desondanks | derhalve; aangezien; indien
+			___ uw vraag van 3 mei … (in response to) | Naar aanleiding van | In verband met; Ten gevolge van; Ondanks
+			Formal close: Met vriendelijke ___ | groet | hoogachting; dank; wensen
+		`
+		}),
+		lesson({
+			id: 'nl-werkwoordclusters',
+			title: 'Heeft moeten doen',
+			summary: 'Verb clusters and the double infinitive',
+			notes: `
+			When a modal (or *laten, gaan, blijven, zien, horen*) appears in the perfect, its participle becomes an **infinitive** (*infinitivus pro participio*):
+
+			- *Ik **heb** moeten werken.* — not ~~gemoeten~~
+			- *Hij **heeft** het niet kunnen vinden.* — He couldn't find it.
+			- *We **hebben** een taxi laten komen.* — We had a taxi come.
+			- *Ze **is** blijven slapen.* — She stayed over.
+
+			In subordinate clauses, all verbs cluster at the end, usually with the finite verb first:
+			*…omdat ik **heb moeten werken**.* / *…dat hij het **had kunnen weten**.*
+
+			Longer clusters are grammatical but heavy:
+			*Hij **zou** het **hebben kunnen doen**.* — He could have done it.
+		`,
+			words: `
+			heb moeten | had to
+			heeft kunnen | was able to
+			had willen | would have wanted to
+			laten | to let; to have (something done)
+			blijven | to stay; to keep (doing)
+			zou hebben kunnen | could have
+			had moeten | should have
+			laten weten | to let know
+			laten zien | to show
+			leren kennen | to get to know
+		`,
+			sentences: `
+			Ik heb gisteren moeten werken. | I had to work yesterday.
+			Hij heeft het niet kunnen vinden. | He couldn't find it.
+			We hebben een pizza laten bezorgen. | We had a pizza delivered.
+			Ze is bij ons blijven eten. | She stayed for dinner at our place.
+			Je had het me moeten vertellen. | You should have told me.
+			Ik weet dat hij het had kunnen weten. | I know he could have known.
+			Waar heb je haar leren kennen? | Where did you get to know her?
+			Laat me even weten of je komt. | Just let me know if you're coming.
+		`,
+			drills: `
+			Ik heb hard ___ werken. | moeten | gemoeten; moet; te moeten | Double infinitive: no ge-.
+			Hij heeft niet ___ komen. | kunnen | gekund; kan; te kunnen
+			We hebben de auto ___ repareren. (had it repaired) | laten | gelaten; laat; te laten
+			Je ___ het me moeten zeggen. (should have) | had | hebt; zou; was
+			…omdat ik gisteren ___. | heb moeten werken | moeten heb werken; werken heb gemoeten; heb gemoeten werken
+		`
+		}),
+		lesson({
+			id: 'nl-valse-vrienden',
+			title: 'Valse vrienden',
+			summary: 'False friends between Dutch and English',
+			notes: `
+			These look like English words but mean something else:
+
+			| Dutch | means | not |
+			|---|---|---|
+			| eventueel | possibly, if necessary | eventually (= uiteindelijk) |
+			| actueel | current, topical | actual (= werkelijk) |
+			| brutaal | cheeky, rude | brutal (= wreed) |
+			| sympathiek | likeable, nice | sympathetic (= meelevend) |
+			| slim | clever | slim (= slank) |
+			| bellen | to call (phone) | to ring a bell only |
+			| bekomen | to recover (from a shock) | become (= worden) |
+			| door | through; by | door (= deur) |
+			| raar | strange | rare (= zeldzaam) |
+			| lust | to like (food) | lust (= begeerte) |
+			| winkel | shop | winkle |
+			| wandelen | to walk, stroll | to wander (= dwalen) |
+			| monster | sample (also: monster) | |
+					`,
+			words: `
+			eventueel | possibly; if necessary
+			uiteindelijk | eventually; in the end
+			actueel | current; topical
+			werkelijk | actual; real
+			brutaal | cheeky; rude
+			wreed | cruel; brutal
+			sympathiek | likeable; nice
+			slim | clever
+			slank | slim
+			raar | strange; weird
+			zeldzaam | rare
+			wandelen | to walk; to stroll
+			het monster | the sample; the monster
+			bekomen | to recover (from a shock)
+		`,
+			sentences: `
+			Eventueel kunnen we morgen afspreken. | If need be, we can meet tomorrow.
+			Uiteindelijk heeft hij toch gewonnen. | In the end he won after all.
+			Dat is een heel actueel onderwerp. | That's a very topical subject.
+			Wat een brutaal kind! | What a cheeky child!
+			Ze is heel sympathiek. | She's very likeable.
+			Hij is erg slim. | He's very clever.
+			Wat een raar verhaal. | What a strange story.
+			Ik moet even bekomen van de schrik. | I need a moment to recover from the shock.
+		`,
+			drills: `
+			"Eventually" in Dutch: ___ | uiteindelijk | eventueel; actueel; eindelijk
+			"Actual" in Dutch: ___ | werkelijk | actueel; eventueel; actief
+			Hij is ___: hij haalt altijd een tien. (clever) | slim | slank; sympathiek; brutaal
+			"Rare" (uncommon) in Dutch: ___ | zeldzaam | raar; rauw; weinig raar
+			Een ___ kind geeft een grote mond. (cheeky) | brutaal | wreed; sympathiek; slim
+		`
+		}),
+		lesson({
+			id: 'nl-abstract',
+			title: 'Abstracte begrippen',
+			summary: 'Abstract vocabulary for discussion and debate',
+			notes: `
+			Nouns ending in **-ing** are de-words and usually come from verbs: *ontwikkelen → de ontwikkeling*, *veranderen → de verandering*.
+			Nouns ending in **-heid** are de-words from adjectives: *vrij → de vrijheid*, *gezond → de gezondheid*.
+			Nouns with **ge-…-te** are het-words and collective: *het gebergte*, *het gebladerte*.
+
+			Useful debate phrases:
+			- *Enerzijds … anderzijds …* — on the one hand … on the other hand …
+			- *Het valt niet te ontkennen dat …* — It can't be denied that …
+			- *Dat hangt af van …* — That depends on …
+			- *Kortom, …* — In short, …
+		`,
+			words: `
+			de ontwikkeling | the development
+			de verandering | the change
+			de vrijheid | the freedom
+			de verantwoordelijkheid | the responsibility
+			de gelijkheid | equality
+			de invloed | the influence
+			het gevolg | the consequence
+			de oorzaak | the cause
+			de uitdaging | the challenge
+			het beleid | the policy
+			de samenleving | society
+			duurzaam | sustainable
+			enerzijds | on the one hand
+			anderzijds | on the other hand
+			kortom | in short
+			ontkennen | to deny
+			benadrukken | to emphasise
+			aantonen | to demonstrate
+		`,
+			sentences: `
+			Enerzijds is het goedkoop, anderzijds is het slecht voor het milieu. | On the one hand it's cheap, on the other hand it's bad for the environment.
+			Het valt niet te ontkennen dat er een probleem is. | It can't be denied that there's a problem.
+			Dat heeft grote gevolgen voor de samenleving. | That has major consequences for society.
+			Wat is de oorzaak van het probleem? | What is the cause of the problem?
+			Het onderzoek toont aan dat het werkt. | The research shows that it works.
+			Kortom, we moeten ons beleid veranderen. | In short, we must change our policy.
+			Iedereen draagt verantwoordelijkheid. | Everyone bears responsibility.
+		`,
+			drills: `
+			___ ontwikkeling | de | het | -ing nouns are de-words.
+			___ vrijheid | de | het | -heid nouns are de-words.
+			Enerzijds is het goed, ___ is het duur. | anderzijds | enerzijds; bovendien; kortom
+			Het onderzoek ___ aan dat het werkt. | toont | laat; wijst; geeft | Aantonen is separable.
+		`
+		}),
+		lesson({
+			id: 'nl-collocaties',
+			title: 'Vaste combinaties',
+			summary: 'Collocations: which verb goes with which noun',
+			notes: `
+			Many nouns take a fixed verb. Translating the English verb often goes wrong:
+
+			| Dutch | English |
+			|---|---|
+			| een besluit **nemen** | to make a decision |
+			| een foto **maken** | to take a photo |
+			| een vraag **stellen** | to ask a question |
+			| rekening **houden** met | to take into account |
+			| een afspraak **maken** | to make an appointment |
+			| aandacht **besteden** aan | to pay attention to |
+			| een rol **spelen** | to play a role |
+			| een fout **maken** | to make a mistake |
+			| contact **opnemen** met | to get in touch with |
+			| een beslissing **nemen** | to take a decision |
+			| indruk **maken** op | to impress |
+			| ontslag **nemen** | to resign |
+			| moeite **doen** | to make an effort |
+		`,
+			words: `
+			een besluit nemen | to make a decision
+			een vraag stellen | to ask a question
+			rekening houden met | to take into account
+			aandacht besteden aan | to pay attention to
+			een rol spelen | to play a role
+			contact opnemen met | to get in touch with
+			indruk maken op | to impress
+			ontslag nemen | to resign
+			moeite doen | to make an effort
+			in aanmerking komen voor | to be eligible for
+			ter sprake komen | to come up (in conversation)
+			op de hoogte houden | to keep informed
+		`,
+			sentences: `
+			We moeten vandaag een besluit nemen. | We have to make a decision today.
+			Mag ik een vraag stellen? | May I ask a question?
+			Houd rekening met vertraging. | Take delays into account.
+			Geld speelt geen rol. | Money is no object.
+			Ik neem morgen contact met u op. | I'll get in touch with you tomorrow.
+			Hij heeft ontslag genomen. | He has resigned.
+			Houd me op de hoogte! | Keep me posted!
+			Dat onderwerp kwam niet ter sprake. | That subject didn't come up.
+		`,
+			drills: `
+			een vraag ___ (to ask) | stellen | vragen; maken; doen
+			een besluit ___ (to make) | nemen | maken; doen; stellen
+			een foto ___ (to take) | maken | nemen; schieten; doen
+			___ houden met (take into account) | rekening | aandacht; indruk; moeite
+			Hij heeft veel indruk op me ___. | gemaakt | gedaan; genomen; gelaten
+		`
+		}),
+		lesson({
+			id: 'nl-spreekwoorden',
+			title: 'Spreekwoorden',
+			summary: 'Proverbs and sayings',
+			notes: `
+			| proverb | meaning |
+			|---|---|
+			| Wie niet waagt, wie niet wint. | Nothing ventured, nothing gained. |
+			| Oost west, thuis best. | There's no place like home. |
+			| Beter een vogel in de hand dan tien in de lucht. | A bird in the hand is worth two in the bush. |
+			| Doe maar normaal, dan doe je al gek genoeg. | Just act normal, that's crazy enough. (very Dutch!) |
+			| Wie het laatst lacht, lacht het best. | He who laughs last laughs best. |
+			| Geen woorden maar daden. | Actions speak louder than words. |
+			| Zo vader, zo zoon. | Like father, like son. |
+			| Als de kat van huis is, dansen de muizen op tafel. | When the cat's away, the mice will play. |
+			| Hoge bomen vangen veel wind. | Tall trees catch a lot of wind (prominence invites criticism). |
+			| Een ezel stoot zich in het gemeen niet twee keer aan dezelfde steen. | A donkey doesn't hit the same stone twice. |
+		`,
+			words: `
+			wie niet waagt, wie niet wint | nothing ventured, nothing gained
+			oost west, thuis best | there's no place like home
+			geen woorden maar daden | actions speak louder than words
+			zo vader, zo zoon | like father, like son
+			doe maar normaal | just act normal
+			hoge bomen vangen veel wind | tall trees catch a lot of wind
+			wie het laatst lacht, lacht het best | he who laughs last laughs best
+			het spreekwoord | the proverb
+		`,
+			sentences: `
+			Doe maar normaal, dan doe je al gek genoeg. | Just act normal, that's crazy enough.
+			Beter een vogel in de hand dan tien in de lucht. | A bird in the hand is worth two in the bush.
+			Als de kat van huis is, dansen de muizen op tafel. | When the cat's away, the mice will play.
+			Na de vakantie dacht ik: oost west, thuis best. | After the holiday I thought: there's no place like home.
+		`,
+			drills: `
+			Wie niet waagt, wie niet ___ | wint | verliest; wacht; weet
+			Oost west, thuis ___ | best | rust; goed; mooi
+			Beter een vogel in de hand dan tien in de ___ | lucht | boom; tuin; wolken
+			Als de kat van huis is, dansen de ___ op tafel | muizen | honden; ratten; vogels
+		`
+		})
+	]
+);

src/lib/language-learner/courses/nl/index.ts

@@ -0,0 +1,18 @@
+import { course } from '../../course';
+import a1 from './a1';
+import a2 from './a2';
+import b1 from './b1';
+import b2 from './b2';
+import c1 from './c1';
+
+export default course(
+	{
+		code: 'nl',
+		name: 'Dutch',
+		nativeName: 'Nederlands',
+		glossLang: 'en',
+		voice: 'nl-NL',
+		tagline: 'From "hallo" to reading the news, taught in English.'
+	},
+	[a1, a2, b1, b2, c1]
+);

src/lib/language-learner/drills/en.ts

@@ -0,0 +1,455 @@
+import { englishNumber } from '../numbers';
+import { int, pick } from '../random';
+import { ask, type DrillMode } from './shared';
+
+type Irregular = {
+	base: string;
+	past: string[];
+	participle: string[];
+	gloss: string;
+	level: number;
+};
+
+const irregulars = (level: number, source: string): Irregular[] =>
+	source
+		.trim()
+		.split('\n')
+		.map((line) => {
+			const [base, past, participle, gloss] = line.split('|').map((p) => p.trim());
+			return { base, past: past.split(';'), participle: participle.split(';'), gloss, level };
+		});
+
+export const IRREGULAR_VERBS: Irregular[] = [
+	...irregulars(
+		1,
+		`
+be|was;were|been|zijn
+have|had|had|hebben
+do|did|done|doen
+go|went|gone|gaan
+come|came|come|komen
+see|saw|seen|zien
+eat|ate|eaten|eten
+drink|drank|drunk|drinken
+make|made|made|maken
+get|got|got;gotten|krijgen, worden
+give|gave|given|geven
+take|took|taken|nemen
+say|said|said|zeggen
+know|knew|known|weten, kennen
+think|thought|thought|denken
+buy|bought|bought|kopen
+read|read|read|lezen
+write|wrote|written|schrijven
+speak|spoke|spoken|spreken
+sleep|slept|slept|slapen
+`
+	),
+	...irregulars(
+		2,
+		`
+begin|began|begun|beginnen
+bring|brought|brought|brengen
+build|built|built|bouwen
+catch|caught|caught|vangen
+choose|chose|chosen|kiezen
+drive|drove|driven|rijden
+fall|fell|fallen|vallen
+feel|felt|felt|voelen
+find|found|found|vinden
+fly|flew|flown|vliegen
+forget|forgot|forgotten|vergeten
+hear|heard|heard|horen
+keep|kept|kept|houden
+leave|left|left|vertrekken, verlaten
+lose|lost|lost|verliezen
+meet|met|met|ontmoeten
+pay|paid|paid|betalen
+put|put|put|leggen, zetten
+run|ran|run|rennen
+sell|sold|sold|verkopen
+send|sent|sent|sturen
+sing|sang|sung|zingen
+sit|sat|sat|zitten
+stand|stood|stood|staan
+swim|swam|swum|zwemmen
+teach|taught|taught|onderwijzen
+tell|told|told|vertellen
+understand|understood|understood|begrijpen
+wear|wore|worn|dragen (kleding)
+win|won|won|winnen
+`
+	),
+	...irregulars(
+		3,
+		`
+bear|bore|borne;born|dragen, verdragen
+beat|beat|beaten|verslaan
+bend|bent|bent|buigen
+bet|bet|bet|wedden
+bite|bit|bitten|bijten
+blow|blew|blown|blazen
+break|broke|broken|breken
+feed|fed|fed|voeren
+fight|fought|fought|vechten
+forgive|forgave|forgiven|vergeven
+freeze|froze|frozen|bevriezen
+grow|grew|grown|groeien
+hang|hung|hung|hangen
+hide|hid|hidden|verstoppen
+hold|held|held|vasthouden
+hurt|hurt|hurt|pijn doen
+lay|laid|laid|leggen
+lead|led|led|leiden
+lend|lent|lent|uitlenen
+lie|lay|lain|liggen
+ride|rode|ridden|rijden (fiets, paard)
+ring|rang|rung|bellen, luiden
+rise|rose|risen|opstaan, stijgen
+seek|sought|sought|zoeken
+shake|shook|shaken|schudden
+shine|shone|shone|schijnen
+shoot|shot|shot|schieten
+shut|shut|shut|sluiten
+sink|sank|sunk|zinken
+spend|spent|spent|uitgeven, doorbrengen
+spread|spread|spread|verspreiden
+steal|stole|stolen|stelen
+stick|stuck|stuck|plakken
+strike|struck|struck|slaan, staken
+swear|swore|sworn|zweren, vloeken
+tear|tore|torn|scheuren
+throw|threw|thrown|gooien
+wake|woke|woken|wakker worden
+`
+	),
+	...irregulars(
+		4,
+		`
+arise|arose|arisen|ontstaan
+bind|bound|bound|binden
+breed|bred|bred|fokken
+cling|clung|clung|zich vastklampen
+creep|crept|crept|kruipen
+dwell|dwelt;dwelled|dwelt;dwelled|verblijven
+flee|fled|fled|vluchten
+forbid|forbade|forbidden|verbieden
+foresee|foresaw|foreseen|voorzien
+grind|ground|ground|malen
+kneel|knelt;kneeled|knelt;kneeled|knielen
+leap|leapt;leaped|leapt;leaped|springen
+mislead|misled|misled|misleiden
+overcome|overcame|overcome|overwinnen
+sew|sewed|sewn;sewed|naaien
+shrink|shrank|shrunk|krimpen
+slide|slid|slid|glijden
+sting|stung|stung|steken (insect)
+stride|strode|stridden|schrijden
+strive|strove;strived|striven;strived|streven
+swell|swelled|swollen;swelled|zwellen
+tread|trod|trodden|betreden
+undertake|undertook|undertaken|ondernemen
+weave|wove|woven|weven
+withdraw|withdrew|withdrawn|terugtrekken
+wring|wrung|wrung|uitwringen
+`
+	)
+];
+
+type Comparison = {
+	adj: string;
+	comparative: string[];
+	superlative: string[];
+	gloss: string;
+	level: number;
+};
+
+const comparisons = (level: number, source: string): Comparison[] =>
+	source
+		.trim()
+		.split('\n')
+		.map((line) => {
+			const [adj, comparative, superlative, gloss] = line.split('|').map((p) => p.trim());
+			return {
+				adj,
+				comparative: comparative.split(';'),
+				superlative: superlative.split(';'),
+				gloss,
+				level
+			};
+		});
+
+const COMPARISONS: Comparison[] = [
+	...comparisons(
+		1,
+		`
+big|bigger|biggest|groot
+small|smaller|smallest|klein
+tall|taller|tallest|lang (persoon)
+old|older|oldest|oud
+young|younger|youngest|jong
+long|longer|longest|lang
+fast|faster|fastest|snel
+cheap|cheaper|cheapest|goedkoop
+hot|hotter|hottest|heet
+happy|happier|happiest|blij
+easy|easier|easiest|makkelijk
+good|better|best|goed
+bad|worse|worst|slecht
+nice|nicer|nicest|leuk, aardig
+beautiful|more beautiful|most beautiful|mooi
+expensive|more expensive|most expensive|duur
+`
+	),
+	...comparisons(
+		2,
+		`
+busy|busier|busiest|druk
+funny|funnier|funniest|grappig
+heavy|heavier|heaviest|zwaar
+early|earlier|earliest|vroeg
+far|farther;further|farthest;furthest|ver
+little|less|least|weinig
+much|more|most|veel
+thin|thinner|thinnest|dun
+wet|wetter|wettest|nat
+sad|sadder|saddest|verdrietig
+large|larger|largest|groot
+safe|safer|safest|veilig
+simple|simpler;more simple|simplest;most simple|eenvoudig
+quiet|quieter|quietest|stil
+interesting|more interesting|most interesting|interessant
+important|more important|most important|belangrijk
+difficult|more difficult|most difficult|moeilijk
+dangerous|more dangerous|most dangerous|gevaarlijk
+comfortable|more comfortable|most comfortable|comfortabel
+famous|more famous|most famous|beroemd
+careful|more careful|most careful|voorzichtig
+boring|more boring|most boring|saai
+modern|more modern|most modern|modern
+`
+	)
+];
+
+type Article = { article: 'a' | 'an'; word: string; gloss: string; why?: string };
+
+const ARTICLES: Article[] = `
+an|apple|appel
+a|banana|banaan
+an|egg|ei
+an|hour|uur|The h is silent: "an our".
+a|house|huis
+a|university|universiteit|"University" starts with a "y" sound: "a you-niversity".
+an|umbrella|paraplu
+a|European|Europeaan|"European" starts with a "y" sound.
+an|honest man|eerlijke man|The h is silent in "honest".
+a|one-way ticket|enkeltje|"One" starts with a "w" sound.
+an|MP|parlementslid|You say "em-pee", which starts with a vowel sound.
+a|UFO|ufo|You say "you-eff-oh".
+an|idea|idee
+a|year|jaar
+an|X-ray|röntgenfoto|You say "eks-ray".
+a|unicorn|eenhoorn
+an|heir|erfgenaam|The h is silent in "heir".
+a|uniform|uniform
+an|orange|sinaasappel
+a|dog|hond
+an|elephant|olifant
+a|user|gebruiker
+an|ice cream|ijsje
+a|euro|euro
+an|owl|uil
+a|hotel|hotel
+an|FBI agent|FBI-agent|You say "eff-bee-eye".
+a|useful tip|nuttige tip
+an|interesting book|interessant boek
+a|horrible day|vreselijke dag
+an|hourly rate|uurtarief
+a|history lesson|geschiedenisles
+an|old friend|oude vriend
+a|yellow car|gele auto
+an|unusual name|ongewone naam
+a|one-euro coin|munt van één euro
+`
+	.trim()
+	.split('\n')
+	.map((line) => {
+		const [article, word, gloss, why] = line.split('|');
+		return { article: article as 'a' | 'an', word, gloss, why };
+	});
+
+const TIME_WORDS = [
+	'twelve',
+	'one',
+	'two',
+	'three',
+	'four',
+	'five',
+	'six',
+	'seven',
+	'eight',
+	'nine',
+	'ten',
+	'eleven',
+	'twelve'
+];
+
+export function englishTime(hour: number, minute: number): string[] {
+	const h = TIME_WORDS[hour % 12 || 12];
+	const next = TIME_WORDS[(hour % 12) + 1];
+	const digital =
+		minute === 0
+			? `${h} o'clock`
+			: `${h} ${minute < 10 ? 'oh ' + englishNumber(minute) : englishNumber(minute)}`;
+	if (minute === 0) return [digital];
+	if (minute === 15) return [`quarter past ${h}`, `a quarter past ${h}`, digital];
+	if (minute === 30) return [`half past ${h}`, digital];
+	if (minute === 45) return [`quarter to ${next}`, `a quarter to ${next}`, digital];
+	if (minute % 5 === 0) {
+		const m = minute < 30 ? minute : 60 - minute;
+		const word = englishNumber(m);
+		return [minute < 30 ? `${word} past ${h}` : `${word} to ${next}`, digital];
+	}
+	return [digital];
+}
+
+export const drills: DrillMode[] = [
+	{
+		id: 'irregular',
+		title: 'Irregular verbs',
+		description:
+			'Past simple and past participle of the irregular verbs, from "go, went, gone" upwards.',
+		make: (ctx) => {
+			const verb = pick(
+				ctx.rng,
+				IRREGULAR_VERBS.filter((v) => v.level <= ctx.level)
+			);
+			const participle = ctx.rng() < 0.5;
+			const answer = participle ? verb.participle : verb.past;
+			const b = verb.base;
+			const regular = b.endsWith('e')
+				? b + 'd'
+				: b.endsWith('y')
+					? b.slice(0, -1) + 'ied'
+					: b + 'ed';
+			return ask(ctx, {
+				skill: participle ? 'irregular-participle' : 'irregular-past',
+				instruction: participle ? 'Past participle (I have …)' : 'Past simple (yesterday I …)',
+				prompt: b,
+				promptLang: 'target',
+				context: verb.gloss,
+				answer,
+				wrong: [
+					regular,
+					...(participle ? verb.past : verb.participle),
+					b,
+					b + 's',
+					regular.replace(/ed$/, 'en')
+				],
+				audio: answer[0]
+			});
+		}
+	},
+	{
+		id: 'comparatives',
+		title: 'Comparatives',
+		description: 'bigger, the biggest, more beautiful, better, worst: -er/-est or more/most.',
+		make: (ctx) => {
+			const adj = pick(
+				ctx.rng,
+				COMPARISONS.filter((c) => c.level <= ctx.level)
+			);
+			const superlative = ctx.rng() < 0.5;
+			const answer = superlative ? adj.superlative : adj.comparative;
+			const a = adj.adj;
+			return ask(ctx, {
+				skill: superlative ? 'comparatives-superlative' : 'comparatives-comparative',
+				instruction: superlative ? 'Superlative (the … -est)' : 'Comparative (… -er than)',
+				prompt: a,
+				promptLang: 'target',
+				context: adj.gloss,
+				answer: superlative ? answer.flatMap((s) => [s, `the ${s}`]) : answer,
+				wrong: superlative
+					? [a + 'est', `most ${a}`, `${a}est`.replace(/yest$/, 'iest'), adj.comparative[0]]
+					: [
+							a + 'er',
+							`more ${a}`,
+							a.replace(/([^aeiou])$/, '$1$1') + 'er',
+							`${a}er`.replace(/yer$/, 'ier')
+						],
+				explain:
+					a.length > 6 && !/y$/.test(a)
+						? 'Long adjectives use more/most instead of -er/-est.'
+						: undefined
+			});
+		}
+	},
+	{
+		id: 'articles',
+		title: 'A or an',
+		description: 'It is about the sound, not the letter: an hour, a university.',
+		make: (ctx) => {
+			const item = pick(ctx.rng, ARTICLES);
+			return ask(ctx, {
+				skill: 'articles',
+				instruction: 'A or an?',
+				prompt: `___ ${item.word}`,
+				promptLang: 'target',
+				context: item.gloss,
+				answer: [item.article],
+				wrong: [item.article === 'a' ? 'an' : 'a'],
+				choice: true,
+				audio: `${item.article} ${item.word}`,
+				explain:
+					item.why ??
+					`"${item.word}" starts with a ${item.article === 'an' ? 'vowel' : 'consonant'} sound.`
+			});
+		}
+	},
+	{
+		id: 'numbers',
+		title: 'Numbers',
+		description: 'Write numbers in words, from seven to seven million.',
+		make: (ctx) => {
+			const max = [20, 100, 1000, 10000, 5_000_000][Math.min(ctx.level, 5) - 1];
+			const n = int(ctx.rng, 0, max);
+			const answer = englishNumber(n);
+			return ask(ctx, {
+				skill: 'numbers',
+				instruction: 'Write this number in English',
+				prompt: n.toLocaleString('en-GB'),
+				answer: [answer, answer.replace(/ and /g, ' ')],
+				wrong: [n + 1, Math.max(0, n - 1), n + 10, n * 10]
+					.filter((m) => m !== n)
+					.map(englishNumber),
+				audio: answer,
+				explain:
+					n > 100 ? 'British English adds "and" before the tens: one hundred and five.' : undefined
+			});
+		}
+	},
+	{
+		id: 'clock',
+		title: 'Telling time',
+		description: '"Half past two" is 2:30, not half drie. Practise both styles.',
+		make: (ctx) => {
+			const hour = int(ctx.rng, 1, 12);
+			const minute = ctx.level <= 1 ? pick(ctx.rng, [0, 15, 30, 45]) : int(ctx.rng, 0, 11) * 5;
+			const answer = englishTime(hour, minute);
+			const shift = (h: number) => ((h + 11) % 12) + 1;
+			return ask(ctx, {
+				skill: 'clock',
+				instruction: 'How do you say this time in English?',
+				prompt: `${hour}:${String(minute).padStart(2, '0')}`,
+				answer,
+				wrong: [
+					englishTime(shift(hour + 1), minute)[0],
+					englishTime(shift(hour - 1), minute)[0],
+					englishTime(hour, (minute + 30) % 60)[0]
+				],
+				audio: answer[0],
+				explain: minute === 30 ? 'Dutch "half drie" is English "half past two".' : undefined
+			});
+		}
+	}
+];

src/lib/language-learner/drills/index.ts

@@ -0,0 +1,14 @@
+import type { LangCode } from '../types';
+import type { DrillMode } from './shared';
+
+export type { DrillMode, DrillContext } from './shared';
+
+const loaders: Record<LangCode, () => Promise<{ drills: DrillMode[] }>> = {
+	nl: () => import('./nl'),
+	ko: () => import('./ko'),
+	en: () => import('./en')
+};
+
+export async function loadDrills(code: LangCode): Promise<DrillMode[]> {
+	return (await loaders[code]()).drills;
+}

src/lib/language-learner/drills/ko.ts

@@ -0,0 +1,382 @@
+import { compose, FINALS, lastSyllable, particle, romanize, type Particle } from '../hangul';
+import {
+	ACTION_FORMS,
+	conjugate,
+	DESCRIPTIVE_FORMS,
+	FORM_LABELS,
+	infinitive,
+	KOREAN_VERBS,
+	type KoreanVerb
+} from '../korean-verbs';
+import { nativeKorean, sinoKorean } from '../numbers';
+import { int, pick, sample } from '../random';
+import { ask, withAndWithoutSpaces, type DrillContext, type DrillMode } from './shared';
+
+const BASIC_CONSONANTS = [...'ㄱㄴㄷㄹㅁㅂㅅㅇㅈㅎ'];
+const EXTRA_CONSONANTS = [...'ㅋㅌㅍㅊㄲㄸㅃㅆㅉ'];
+const BASIC_VOWELS = [...'ㅏㅓㅗㅜㅡㅣ'];
+const EXTRA_VOWELS = [...'ㅐㅔㅑㅕㅛㅠㅘㅝㅚㅟㅢㅙㅞㅒㅖ'];
+const SIMPLE_FINALS = [...'ㄱㄴㄷㄹㅁㅂㅇ'];
+const MORE_FINALS = [...'ㅅㅈㅊㅋㅌㅍㅎㄲㅆ'];
+
+function randomSyllable(ctx: DrillContext): string {
+	const { rng, level } = ctx;
+	const initials = level >= 2 ? [...BASIC_CONSONANTS, ...EXTRA_CONSONANTS] : BASIC_CONSONANTS;
+	const vowels = level >= 3 ? [...BASIC_VOWELS, ...EXTRA_VOWELS] : BASIC_VOWELS;
+	const finals = level >= 5 ? [...SIMPLE_FINALS, ...MORE_FINALS] : SIMPLE_FINALS;
+	const final = level >= 4 && rng() < 0.6 ? pick(rng, finals) : '';
+	return compose({
+		initial: pick(rng, initials),
+		medial: pick(rng, vowels),
+		final: FINALS.includes(final) ? final : ''
+	});
+}
+
+type Noun = { word: string; gloss: string };
+
+const NOUNS: Noun[] = `
+학생|student
+선생님|teacher
+친구|friend
+책|book
+사과|apple
+물|water
+커피|coffee
+우유|milk
+가방|bag
+집|house
+학교|school
+회사|company
+병원|hospital
+은행|bank
+시장|market
+서울|Seoul
+부산|Busan
+한국|Korea
+영어|English
+한국어|Korean (language)
+음식|food
+밥|rice, meal
+김치|kimchi
+빵|bread
+차|car, tea
+버스|bus
+지하철|subway
+비행기|airplane
+컴퓨터|computer
+사람|person
+이름|name
+가족|family
+어머니|mother
+아버지|father
+동생|younger sibling
+개|dog
+고양이|cat
+날씨|weather
+영화|movie
+음악|music
+노래|song
+사진|photo
+돈|money
+시간|time
+옷|clothes
+신발|shoes
+모자|hat
+연필|pencil
+의자|chair
+문|door
+방|room
+화장실|bathroom
+도서관|library
+공원|park
+바다|sea
+산|mountain
+편지|letter
+선물|present
+생일|birthday
+지갑|wallet
+`
+	.trim()
+	.split('\n')
+	.map((line) => {
+		const [word, gloss] = line.split('|');
+		return { word, gloss };
+	});
+
+const PARTICLES: { kind: Particle; label: string; level: number; pair: [string, string] }[] = [
+	{ kind: 'topic', label: 'topic (은/는)', level: 1, pair: ['은', '는'] },
+	{ kind: 'subject', label: 'subject (이/가)', level: 1, pair: ['이', '가'] },
+	{ kind: 'object', label: 'object (을/를)', level: 1, pair: ['을', '를'] },
+	{ kind: 'copula', label: '"it is" (이에요/예요)', level: 1, pair: ['이에요', '예요'] },
+	{ kind: 'and', label: '"and" (과/와)', level: 2, pair: ['과', '와'] },
+	{ kind: 'with', label: '"with/and", casual (이랑/랑)', level: 2, pair: ['이랑', '랑'] },
+	{ kind: 'direction', label: '"towards/by" ((으)로)', level: 3, pair: ['으로', '로'] }
+];
+
+/** Mistakes a learner is likely to make: ignoring an irregular, or the wrong vowel. */
+function verbMistakes(verb: KoreanVerb, form: (typeof ACTION_FORMS)[number]): string[] {
+	const stem = verb.dict.slice(0, -1);
+	const variants: KoreanVerb[] = [
+		{ ...verb, irr: undefined },
+		...(['b', 'd', 'reu', 's', 'h'] as const)
+			.filter((i) => i !== verb.irr)
+			.map((irr) => ({ ...verb, irr }))
+	];
+	const wrong = variants.flatMap((v) => {
+		try {
+			return conjugate(v, form);
+		} catch {
+			return [];
+		}
+	});
+	const inf = infinitive(verb);
+	const flipped = inf.endsWith('아')
+		? inf.slice(0, -1) + '어'
+		: inf.endsWith('어')
+			? inf.slice(0, -1) + '아'
+			: inf;
+	if (form === 'present') wrong.push(flipped + '요', stem + '어요', stem + '아요');
+	if (form === 'past')
+		wrong.push(
+			stem + '었어요',
+			stem + '았어요',
+			flipped.replace(/[아어]$/, (v) => (v === '아' ? '았' : '었')) + '어요'
+		);
+	if (form === 'formal') wrong.push(stem + '습니다', stem + 'ㅂ니다', stem + '니다');
+	if (form === 'future') wrong.push(stem + '을 거예요', stem + 'ㄹ 거예요', stem + ' 거예요');
+	const others = (verb.action ? ACTION_FORMS : DESCRIPTIVE_FORMS).filter((f) => f !== form);
+	return [...wrong, ...others.map((f) => conjugate(verb, f)[0])];
+}
+
+type CountTask = { prompt: string; answer: string[]; wrong: string[]; explain: string };
+
+function countTask(ctx: DrillContext): CountTask {
+	const { rng, level } = ctx;
+	const tasks: (() => CountTask)[] = [
+		() => {
+			const n = int(rng, 1, level >= 3 ? 99999 : level >= 2 ? 1000 : 100);
+			return {
+				prompt: `${n.toLocaleString('en-US')} (Sino-Korean)`,
+				answer: [sinoKorean(n)],
+				wrong: [
+					sinoKorean(n + 1),
+					sinoKorean(Math.max(1, n - 1)),
+					sinoKorean(n * 10),
+					sinoKorean(n + 10)
+				],
+				explain: 'Sino-Korean: 일 이 삼 사 오 육 칠 팔 구 십, 백 (100), 천 (1,000), 만 (10,000).'
+			};
+		},
+		() => {
+			const n = int(rng, 1, level >= 2 ? 99 : 10);
+			return {
+				prompt: `${n} (native Korean)`,
+				answer: [nativeKorean(n)],
+				wrong: [
+					nativeKorean(n === 99 ? 98 : n + 1),
+					sinoKorean(n),
+					nativeKorean(n, true),
+					nativeKorean(n > 1 ? n - 1 : 2)
+				],
+				explain:
+					'Native: 하나 둘 셋 넷 다섯 여섯 일곱 여덟 아홉 열, then 스물 서른 마흔 쉰 예순 일흔 여든 아흔.'
+			};
+		},
+		() => {
+			const [counter, gloss] = pick(rng, [
+				['명', 'people'],
+				['개', 'things'],
+				['살', 'years old'],
+				['잔', 'cups'],
+				['병', 'bottles'],
+				['마리', 'animals'],
+				['권', 'books']
+			] as const);
+			const n = int(rng, 1, level >= 2 ? 40 : 10);
+			return {
+				prompt: `${n} ${gloss} (${counter})`,
+				answer: withAndWithoutSpaces([`${nativeKorean(n, true)} ${counter}`]),
+				wrong: [
+					`${nativeKorean(n)} ${counter}`,
+					`${sinoKorean(n)} ${counter}`,
+					`${nativeKorean(n === 40 ? 39 : n + 1, true)} ${counter}`
+				],
+				explain:
+					'Counting things uses native numbers, shortened before a counter: 한, 두, 세, 네, 스무.'
+			};
+		},
+		() => {
+			const hour = int(rng, 1, 12);
+			const minute = level >= 2 ? int(rng, 0, 11) * 5 : pick(rng, [0, 30]);
+			const h = `${nativeKorean(hour, true)} 시`;
+			const answer =
+				minute === 0
+					? [h]
+					: minute === 30
+						? [`${h} 반`, `${h} ${sinoKorean(30)} 분`]
+						: [`${h} ${sinoKorean(minute)} 분`];
+			return {
+				prompt: `${hour}:${String(minute).padStart(2, '0')}`,
+				answer: withAndWithoutSpaces(answer),
+				wrong: [
+					`${sinoKorean(hour)} 시${minute ? ` ${sinoKorean(minute)} 분` : ''}`,
+					`${nativeKorean(hour, true)} 시${minute ? ` ${nativeKorean(Math.min(minute, 99), true)} 분` : ''}`,
+					`${nativeKorean(hour === 12 ? 1 : hour + 1, true)} 시${minute ? ` ${sinoKorean(minute)} 분` : ''}`
+				],
+				explain:
+					'Hours use native numbers (한 시, 두 시), minutes use Sino-Korean (십 분). 반 = half past.'
+			};
+		},
+		() => {
+			const price = int(rng, 1, level >= 2 ? 500 : 50) * 100;
+			return {
+				prompt: `₩${price.toLocaleString('en-US')}`,
+				answer: withAndWithoutSpaces([`${sinoKorean(price)} 원`]),
+				wrong: [
+					`${sinoKorean(price * 10)} 원`,
+					`${sinoKorean(Math.max(100, price - 100))} 원`,
+					`${sinoKorean(price + 1000)} 원`
+				],
+				explain: 'Money uses Sino-Korean numbers. 10,000 is 만, so 50,000 is 오만.'
+			};
+		},
+		() => {
+			const month = int(rng, 1, 12);
+			const name = (m: number) => (m === 6 ? '유월' : m === 10 ? '시월' : `${sinoKorean(m)}월`);
+			const english = new Date(2026, month - 1, 1).toLocaleString('en-US', { month: 'long' });
+			return {
+				prompt: english,
+				answer: [name(month)],
+				wrong: [
+					`${sinoKorean(month)}월`,
+					`${nativeKorean(month, true)} 월`,
+					name((month % 12) + 1)
+				],
+				explain: 'Months are Sino-Korean + 월. June (유월) and October (시월) drop a consonant.'
+			};
+		}
+	];
+	return pick(rng, tasks)();
+}
+
+export const drills: DrillMode[] = [
+	{
+		id: 'hangul',
+		title: 'Hangul reading',
+		description:
+			'Read syllables and real words. Higher levels add tense consonants, compound vowels and batchim.',
+		make: (ctx) => {
+			const words = ctx.course.levels
+				.slice(1, 1 + ctx.level)
+				.flatMap((lv) => lv.lessons.flatMap((ls) => ls.words))
+				.filter((w) => w.kind === 'word' && /^[가-힣]+$/.test(w.target[0]));
+			const useWord = ctx.level >= 3 && words.length && ctx.rng() < 0.5;
+			const text = useWord ? pick(ctx.rng, words).target[0] : randomSyllable(ctx);
+			const answer = romanize(text);
+			if (ctx.rng() < 0.5 || useWord) {
+				const others = Array.from({ length: 8 }, () =>
+					romanize(useWord ? pick(ctx.rng, words).target[0] : randomSyllable(ctx))
+				);
+				return ask(ctx, {
+					skill: 'hangul',
+					instruction: 'How is this read?',
+					prompt: text,
+					promptLang: 'target',
+					answer: [answer],
+					wrong: others,
+					audio: text,
+					explain: useWord ? 'Romanization shows sound changes between syllables.' : undefined
+				});
+			}
+			const others = Array.from({ length: 12 }, () => randomSyllable(ctx)).filter(
+				(s) => romanize(s) !== answer
+			);
+			return ask(ctx, {
+				skill: 'hangul-write',
+				instruction: 'Which syllable is this?',
+				prompt: answer,
+				answer: [text],
+				wrong: others,
+				choice: true,
+				audio: text
+			});
+		}
+	},
+	{
+		id: 'particles',
+		title: 'Particles',
+		description: '은/는, 이/가, 을/를 and friends: pick the form that fits the noun.',
+		make: (ctx) => {
+			const noun = pick(ctx.rng, NOUNS);
+			const p = pick(
+				ctx.rng,
+				PARTICLES.filter((x) => x.level <= ctx.level)
+			);
+			const answer = particle(noun.word, p.kind);
+			const wrong = p.pair.map((form) => noun.word + form).filter((w) => w !== answer);
+			if (p.kind === 'direction') wrong.push(noun.word + '으로', noun.word + '로');
+			return ask(ctx, {
+				skill: 'particles',
+				instruction: `Add the ${p.label} particle`,
+				prompt: noun.word,
+				promptLang: 'target',
+				context: noun.gloss,
+				answer: [answer],
+				wrong,
+				choice: true,
+				audio: answer,
+				explain:
+					p.kind === 'direction' && lastSyllable(noun.word)?.final === 'ㄹ'
+						? 'Nouns ending in ㄹ take 로, not 으로.'
+						: `After a consonant: ${p.pair[0]}; after a vowel: ${p.pair[1]}.`
+			});
+		}
+	},
+	{
+		id: 'verbs',
+		title: 'Conjugation',
+		description: 'Polite, past, future, formal and more, including the ㅂ/ㄷ/르/ㅅ/ㅎ irregulars.',
+		make: (ctx) => {
+			const verb = pick(
+				ctx.rng,
+				KOREAN_VERBS.filter((v) => v.level <= ctx.level)
+			);
+			const available = (verb.action ? ACTION_FORMS : DESCRIPTIVE_FORMS).filter(
+				(f) => ctx.level >= 3 || ['present', 'past', 'future', 'negative', 'want'].includes(f)
+			);
+			const form = pick(ctx.rng, available);
+			const answer = conjugate(verb, form);
+			return ask(ctx, {
+				skill: `verbs-${form}`,
+				instruction: `Conjugate · ${FORM_LABELS[form]}`,
+				prompt: verb.dict,
+				promptLang: 'target',
+				context: verb.gloss,
+				answer: withAndWithoutSpaces(answer),
+				wrong: sample(ctx.rng, verbMistakes(verb, form), 6),
+				audio: answer[0],
+				explain: verb.irr
+					? `${verb.dict} is ${{ b: 'ㅂ', d: 'ㄷ', reu: '르', s: 'ㅅ', h: 'ㅎ' }[verb.irr]}-irregular.`
+					: undefined
+			});
+		}
+	},
+	{
+		id: 'numbers',
+		title: 'Numbers & counters',
+		description:
+			'Two number systems: Sino-Korean for money, dates and minutes; native for counting and hours.',
+		make: (ctx) => {
+			const task = countTask(ctx);
+			return ask(ctx, {
+				skill: 'numbers',
+				instruction: 'Say it in Korean',
+				prompt: task.prompt,
+				answer: task.answer,
+				wrong: task.wrong,
+				audio: task.answer[0],
+				explain: task.explain
+			});
+		}
+	}
+];

src/lib/language-learner/drills/nl.ts

@@ -0,0 +1,592 @@
+import { dutchNumber } from '../numbers';
+import { int, pick } from '../random';
+import { ask, type DrillMode } from './shared';
+
+type Noun = { article: 'de' | 'het'; noun: string; plural: string[]; gloss: string; level: number };
+
+const nouns = (level: number, source: string): Noun[] =>
+	source
+		.trim()
+		.split('\n')
+		.map((line) => {
+			const [word, plural, gloss] = line.split('|').map((p) => p.trim());
+			const [article, noun] = word.split(' ') as ['de' | 'het', string];
+			return { article, noun, plural: plural ? plural.split(';') : [], gloss, level };
+		});
+
+export const DUTCH_NOUNS: Noun[] = [
+	...nouns(
+		1,
+		`
+het huis|huizen|house
+de hond|honden|dog
+de kat|katten|cat
+het boek|boeken|book
+de tafel|tafels|table
+de stoel|stoelen|chair
+het raam|ramen|window
+de deur|deuren|door
+de auto|auto's|car
+de fiets|fietsen|bicycle
+het kind|kinderen|child
+de man|mannen|man
+de vrouw|vrouwen|woman
+het meisje|meisjes|girl
+de jongen|jongens|boy
+de vriend|vrienden|friend
+het water||water
+het brood|broden|bread
+de kaas|kazen|cheese
+het ei|eieren|egg
+de appel|appels|apple
+het glas|glazen|glass
+de stad|steden|city
+het land|landen|country
+de straat|straten|street
+het station|stations|station
+de trein|treinen|train
+de dag|dagen|day
+de week|weken|week
+het jaar|jaren|year
+het uur|uren|hour
+de school|scholen|school
+het bed|bedden|bed
+de kamer|kamers|room
+de moeder|moeders|mother
+de vader|vaders|father
+de zus|zussen|sister
+de broer|broers|brother
+de koffie||coffee
+de thee||tea
+de melk||milk
+het geld||money
+de naam|namen|name
+de telefoon|telefoons|phone
+het oog|ogen|eye
+de hand|handen|hand
+het weer||weather
+de zon||sun
+de maan|manen|moon
+`
+	),
+	...nouns(
+		2,
+		`
+de banaan|bananen|banana
+het bord|borden|plate
+de lepel|lepels|spoon
+het mes|messen|knife
+de vork|vorken|fork
+het dorp|dorpen|village
+de weg|wegen|road
+de bus|bussen|bus
+het vliegtuig|vliegtuigen|airplane
+het schip|schepen|ship
+de maand|maanden|month
+de minuut|minuten|minute
+de les|lessen|lesson
+de leraar|leraren|teacher
+de keuken|keukens|kitchen
+de tuin|tuinen|garden
+de boom|bomen|tree
+de bloem|bloemen|flower
+het dier|dieren|animal
+het paard|paarden|horse
+de koe|koeien|cow
+het varken|varkens|pig
+de vogel|vogels|bird
+de vis|vissen|fish
+het hoofd|hoofden|head
+het oor|oren|ear
+de neus|neuzen|nose
+de mond|monden|mouth
+de voet|voeten|foot
+het been|benen|leg
+het hart|harten|heart
+de dokter|dokters|doctor
+het ziekenhuis|ziekenhuizen|hospital
+de winkel|winkels|shop
+de prijs|prijzen|price
+het bericht|berichten|message
+de brief|brieven|letter
+het woord|woorden|word
+de taal|talen|language
+de vraag|vragen|question
+het antwoord|antwoorden|answer
+de film|films|film
+het lied|liederen|song
+het spel|spellen|game
+het feest|feesten|party
+de verjaardag|verjaardagen|birthday
+het cadeau|cadeaus|present, gift
+de kleur|kleuren|colour
+de zee|zeeën|sea
+het strand|stranden|beach
+de berg|bergen|mountain
+de rivier|rivieren|river
+het bos|bossen|forest
+het eiland|eilanden|island
+het gebouw|gebouwen|building
+de kerk|kerken|church
+het restaurant|restaurants|restaurant
+de rekening|rekeningen|bill
+het menu|menu's|menu
+het bier|bieren|beer
+de wijn|wijnen|wine
+het vlees||meat
+de groente|groenten;groentes|vegetable
+het fruit||fruit
+de soep|soepen|soup
+de broek|broeken|trousers
+het overhemd|overhemden|shirt
+de jas|jassen|coat
+de schoen|schoenen|shoe
+de tas|tassen|bag
+de sleutel|sleutels|key
+het nummer|nummers|number
+het adres|adressen|address
+het gezin|gezinnen|family, household
+het kaartje|kaartjes|ticket
+`
+	),
+	...nouns(
+		3,
+		`
+de baan|banen|job
+het bedrijf|bedrijven|company
+de vergadering|vergaderingen|meeting
+het kantoor|kantoren|office
+de fout|fouten|mistake
+het verhaal|verhalen|story
+de krant|kranten|newspaper
+het nieuws||news
+de regering|regeringen|government
+het beleid||policy
+de ervaring|ervaringen|experience
+het onderzoek|onderzoeken|research
+de oplossing|oplossingen|solution
+het voordeel|voordelen|advantage
+het nadeel|nadelen|disadvantage
+de gewoonte|gewoonten;gewoontes|habit
+het gevoel|gevoelens|feeling
+de mening|meningen|opinion
+het gesprek|gesprekken|conversation
+de toekomst||future
+het verleden||past
+het lichaam|lichamen|body
+de gezondheid||health
+het geluk||luck, happiness
+het museum|musea;museums|museum
+het idee|ideeën|idea
+het probleem|problemen|problem
+de maatschappij|maatschappijen|society
+het onderwerp|onderwerpen|subject, topic
+de ontwikkeling|ontwikkelingen|development
+het gedrag||behaviour
+de invloed|invloeden|influence
+het doel|doelen|goal
+de uitdaging|uitdagingen|challenge
+het verschil|verschillen|difference
+de wet|wetten|law
+het recht|rechten|right, law
+de verkiezing|verkiezingen|election
+het milieu||environment
+de gemeente|gemeenten;gemeentes|municipality
+het gebied|gebieden|area
+de afspraak|afspraken|appointment
+het gevolg|gevolgen|consequence
+de reden|redenen|reason
+het resultaat|resultaten|result
+`
+	)
+];
+
+type Verb = {
+	inf: string;
+	gloss: string;
+	ik: string;
+	jij: string[];
+	hij: string[];
+	past: [string[], string];
+	participle?: string;
+	aux?: 'h' | 'z' | 'hz';
+	level: number;
+};
+
+const verbs = (level: number, source: string): Verb[] =>
+	source
+		.trim()
+		.split('\n')
+		.map((line) => {
+			const [inf, gloss, ik, pastSg, pastPl, participle, aux, present] = line
+				.split('|')
+				.map((p) => p.trim());
+			const regular = ik.endsWith('t') ? ik : ik + 't';
+			const [jij, hij] = present
+				? present.split(',').map((v) => v.split(';'))
+				: [[regular], [regular]];
+			return {
+				inf,
+				gloss,
+				ik,
+				jij,
+				hij,
+				past: [pastSg.split(';'), pastPl],
+				participle: participle || undefined,
+				aux: (aux || undefined) as Verb['aux'],
+				level
+			};
+		});
+
+export const DUTCH_VERBS: Verb[] = [
+	...verbs(
+		1,
+		`
+zijn|to be|ben|was|waren|geweest|z|bent,is
+hebben|to have|heb|had|hadden|gehad|h|hebt,heeft
+gaan|to go|ga|ging|gingen|gegaan|z
+komen|to come|kom|kwam|kwamen|gekomen|z
+doen|to do|doe|deed|deden|gedaan|h
+werken|to work|werk|werkte|werkten|gewerkt|h
+wonen|to live (somewhere)|woon|woonde|woonden|gewoond|h
+spelen|to play|speel|speelde|speelden|gespeeld|h
+maken|to make|maak|maakte|maakten|gemaakt|h
+leren|to learn|leer|leerde|leerden|geleerd|h
+praten|to talk|praat|praatte|praatten|gepraat|h
+koken|to cook|kook|kookte|kookten|gekookt|h
+eten|to eat|eet|at|aten|gegeten|h
+drinken|to drink|drink|dronk|dronken|gedronken|h
+zien|to see|zie|zag|zagen|gezien|h
+lezen|to read|lees|las|lazen|gelezen|h
+kopen|to buy|koop|kocht|kochten|gekocht|h
+kunnen|can, to be able to|kan|kon|konden|||kunt;kan,kan
+willen|to want|wil|wilde;wou|wilden;wouden|||wilt;wil,wil
+moeten|must, to have to|moet|moest|moesten|||
+mogen|may, to be allowed to|mag|mocht|mochten|||mag,mag
+`
+	),
+	...verbs(
+		2,
+		`
+fietsen|to cycle|fiets|fietste|fietsten|gefietst|h
+dansen|to dance|dans|danste|dansten|gedanst|h
+reizen|to travel|reis|reisde|reisden|gereisd|hz
+leven|to live (be alive)|leef|leefde|leefden|geleefd|h
+betalen|to pay|betaal|betaalde|betaalden|betaald|h
+vertellen|to tell|vertel|vertelde|vertelden|verteld|h
+antwoorden|to answer|antwoord|antwoordde|antwoordden|geantwoord|h
+luisteren|to listen|luister|luisterde|luisterden|geluisterd|h
+wachten|to wait|wacht|wachtte|wachtten|gewacht|h
+zetten|to put|zet|zette|zetten|gezet|h
+huren|to rent|huur|huurde|huurden|gehuurd|h
+bellen|to call (phone)|bel|belde|belden|gebeld|h
+stoppen|to stop|stop|stopte|stopten|gestopt|h
+schrijven|to write|schrijf|schreef|schreven|geschreven|h
+spreken|to speak|spreek|sprak|spraken|gesproken|h
+nemen|to take|neem|nam|namen|genomen|h
+geven|to give|geef|gaf|gaven|gegeven|h
+denken|to think|denk|dacht|dachten|gedacht|h
+brengen|to bring|breng|bracht|brachten|gebracht|h
+zoeken|to look for|zoek|zocht|zochten|gezocht|h
+vinden|to find|vind|vond|vonden|gevonden|h
+lopen|to walk|loop|liep|liepen|gelopen|hz
+slapen|to sleep|slaap|sliep|sliepen|geslapen|h
+staan|to stand|sta|stond|stonden|gestaan|h
+zitten|to sit|zit|zat|zaten|gezeten|h
+liggen|to lie (down)|lig|lag|lagen|gelegen|h
+weten|to know (a fact)|weet|wist|wisten|geweten|h
+worden|to become|word|werd|werden|geworden|z
+blijven|to stay|blijf|bleef|bleven|gebleven|z
+vragen|to ask|vraag|vroeg|vroegen|gevraagd|h
+zeggen|to say|zeg|zei|zeiden|gezegd|h
+kijken|to look, to watch|kijk|keek|keken|gekeken|h
+`
+	),
+	...verbs(
+		3,
+		`
+beginnen|to begin|begin|begon|begonnen|begonnen|z
+vergeten|to forget|vergeet|vergat|vergaten|vergeten|hz
+vallen|to fall|val|viel|vielen|gevallen|z
+helpen|to help|help|hielp|hielpen|geholpen|h
+sterven|to die|sterf|stierf|stierven|gestorven|z
+rijden|to drive, to ride|rijd|reed|reden|gereden|hz
+vliegen|to fly|vlieg|vloog|vlogen|gevlogen|hz
+zwemmen|to swim|zwem|zwom|zwommen|gezwommen|hz
+zingen|to sing|zing|zong|zongen|gezongen|h
+winnen|to win|win|won|wonnen|gewonnen|h
+verliezen|to lose|verlies|verloor|verloren|verloren|h
+kiezen|to choose|kies|koos|kozen|gekozen|h
+sluiten|to close|sluit|sloot|sloten|gesloten|h
+bieden|to offer|bied|bood|boden|geboden|h
+dragen|to carry, to wear|draag|droeg|droegen|gedragen|h
+slaan|to hit|sla|sloeg|sloegen|geslagen|h
+lachen|to laugh|lach|lachte|lachten|gelachen|h
+wassen|to wash|was|waste|wasten|gewassen|h
+bakken|to bake|bak|bakte|bakten|gebakken|h
+vriezen|to freeze|vries|vroor|vroren|gevroren|hz
+wegen|to weigh|weeg|woog|wogen|gewogen|h
+bederven|to spoil|bederf|bedierf|bedierven|bedorven|hz
+`
+	)
+];
+
+const PERSONS = [
+	{ label: 'ik', slot: 'ik', plural: false },
+	{ label: 'jij', slot: 'jij', plural: false },
+	{ label: 'hij', slot: 'hij', plural: false },
+	{ label: 'zij (she)', slot: 'hij', plural: false },
+	{ label: 'u', slot: 'jij', plural: false },
+	{ label: 'wij', slot: 'pl', plural: true },
+	{ label: 'jullie', slot: 'pl', plural: true },
+	{ label: 'zij (they)', slot: 'pl', plural: true }
+] as const;
+
+const AUX = {
+	h: { ik: 'heb', jij: 'hebt', hij: 'heeft', pl: 'hebben' },
+	z: { ik: 'ben', jij: 'bent', hij: 'is', pl: 'zijn' }
+};
+
+type Person = (typeof PERSONS)[number];
+
+// "u hebt" and "u heeft", "u kunt" and "u kan" are both correct.
+const U_EITHER = ['hebben', 'kunnen'];
+
+function present(verb: Verb, person: Person): string[] {
+	if (person.slot === 'ik') return [verb.ik];
+	if (person.slot === 'pl') return [verb.inf];
+	if (person.label === 'u' && U_EITHER.includes(verb.inf))
+		return [...new Set([...verb.jij, ...verb.hij])];
+	return person.slot === 'jij' ? verb.jij : verb.hij;
+}
+
+function perfect(verb: Verb, person: Person): string[] {
+	const auxes = verb.aux === 'hz' ? (['h', 'z'] as const) : [verb.aux as 'h' | 'z'];
+	return auxes
+		.flatMap((a) => (person.label === 'u' && a === 'h' ? ['hebt', 'heeft'] : [AUX[a][person.slot]]))
+		.map((aux) => `${aux} ${verb.participle}`);
+}
+
+/** Common learner mistakes, used as wrong options. */
+function mistakes(verb: Verb): string[] {
+	const stem = verb.ik;
+	return [
+		stem + 'de',
+		stem + 'te',
+		stem + 'den',
+		stem + 'ten',
+		'ge' + stem + 'd',
+		'ge' + stem + 't',
+		verb.inf,
+		stem,
+		stem + 't',
+		...verb.past[0],
+		verb.past[1]
+	];
+}
+
+const HOURS = [
+	'twaalf',
+	'een',
+	'twee',
+	'drie',
+	'vier',
+	'vijf',
+	'zes',
+	'zeven',
+	'acht',
+	'negen',
+	'tien',
+	'elf',
+	'twaalf'
+];
+
+/** "half drie" means 2:30: Dutch counts half an hour towards the next hour. */
+export function dutchTime(hour: number, minute: number): string {
+	const h = HOURS[hour % 12 || 12];
+	const next = HOURS[(hour % 12) + 1];
+	const phrases: Record<number, string> = {
+		0: `${h} uur`,
+		5: `vijf over ${h}`,
+		10: `tien over ${h}`,
+		15: `kwart over ${h}`,
+		20: `tien voor half ${next}`,
+		25: `vijf voor half ${next}`,
+		30: `half ${next}`,
+		35: `vijf over half ${next}`,
+		40: `tien over half ${next}`,
+		45: `kwart voor ${next}`,
+		50: `tien voor ${next}`,
+		55: `vijf voor ${next}`
+	};
+	return phrases[minute];
+}
+
+const numberRange = (level: number) => [20, 100, 1000, 10000, 3_000_000][Math.min(level, 5) - 1];
+
+export const drills: DrillMode[] = [
+	{
+		id: 'numbers',
+		title: 'Numbers',
+		description: 'Write numbers out in full, from nul to miljoenen.',
+		make: (ctx) => {
+			const max = numberRange(ctx.level);
+			const n = ctx.level >= 4 && ctx.rng() < 0.3 ? int(ctx.rng, 1900, 2099) : int(ctx.rng, 0, max);
+			const answer = dutchNumber(n);
+			const near = [
+				n + 1,
+				n - 1,
+				n + 10,
+				n - 10,
+				n + 100,
+				Number(String(n).split('').reverse().join(''))
+			];
+			return ask(ctx, {
+				skill: 'numbers',
+				instruction: 'Write this number in Dutch',
+				prompt: n.toLocaleString('nl-NL'),
+				answer: [answer],
+				wrong: near.filter((m) => m >= 0 && m !== n).map(dutchNumber),
+				audio: answer,
+				explain:
+					n > 20 && n < 100 ? 'Units come first: vijfentwintig is "five-and-twenty".' : undefined
+			});
+		}
+	},
+	{
+		id: 'clock',
+		title: 'Telling time',
+		description: '"Half drie" is 2:30. Practise the Dutch clock until it is automatic.',
+		make: (ctx) => {
+			const hour = int(ctx.rng, 1, 12);
+			const minute = ctx.level <= 1 ? pick(ctx.rng, [0, 15, 30, 45]) : int(ctx.rng, 0, 11) * 5;
+			const answer = dutchTime(hour, minute);
+			const other = (h: number, m: number) => dutchTime(((h + 11) % 12) + 1, m);
+			return ask(ctx, {
+				skill: 'clock',
+				instruction: 'How do you say this time in Dutch?',
+				prompt: `${hour}:${String(minute).padStart(2, '0')}`,
+				answer: [answer],
+				wrong: [
+					other(hour - 1, minute),
+					other(hour + 1, minute),
+					other(hour, (minute + 30) % 60),
+					other(hour, (60 - minute) % 60)
+				],
+				audio: answer,
+				explain:
+					minute >= 20 && minute <= 40
+						? '20–40 minutes past are counted around "half" the next hour.'
+						: undefined
+			});
+		}
+	},
+	{
+		id: 'articles',
+		title: 'De or het',
+		description: 'Endless de/het practice. Tip: all plurals and most people are "de".',
+		make: (ctx) => {
+			const noun = pick(
+				ctx.rng,
+				DUTCH_NOUNS.filter((n) => n.level <= ctx.level)
+			);
+			const answer = noun.article;
+			return ask(ctx, {
+				skill: 'articles',
+				instruction: 'De or het?',
+				prompt: `___ ${noun.noun}`,
+				promptLang: 'target',
+				context: noun.gloss,
+				answer: [answer],
+				wrong: [answer === 'de' ? 'het' : 'de'],
+				choice: true,
+				audio: `${noun.article} ${noun.noun}`,
+				explain: noun.noun.endsWith('je') ? 'Diminutives ending in -je are always het.' : undefined
+			});
+		}
+	},
+	{
+		id: 'plurals',
+		title: 'Plurals',
+		description: '-en or -s, and all the spelling changes in between.',
+		make: (ctx) => {
+			const noun = pick(
+				ctx.rng,
+				DUTCH_NOUNS.filter((n) => n.level <= ctx.level && n.plural.length)
+			);
+			const n = noun.noun;
+			const doubled = n.replace(/([^aeiou])$/, '$1$1');
+			const wrong = [
+				n + 'en',
+				n + 's',
+				doubled + 'en',
+				n + 'es',
+				n.replace(/(aa|ee|oo|uu)([^aeiou])$/, (_, v, c) => v[0] + c) + 'en'
+			];
+			return ask(ctx, {
+				skill: 'plurals',
+				instruction: 'Give the plural',
+				prompt: `${noun.article} ${n}`,
+				promptLang: 'target',
+				context: noun.gloss,
+				answer: noun.plural.flatMap((p) => [p, `de ${p}`]),
+				wrong,
+				audio: `de ${noun.plural[0]}`,
+				explain: 'All plurals take "de".'
+			});
+		}
+	},
+	{
+		id: 'verbs',
+		title: 'Verb forms',
+		description: 'Present tense, then the perfect (heb gewerkt) and the simple past (werkte).',
+		make: (ctx) => {
+			const verb = pick(
+				ctx.rng,
+				DUTCH_VERBS.filter((v) => v.level <= ctx.level)
+			);
+			const person = pick(ctx.rng, PERSONS);
+			const tenses = [
+				'present',
+				...(ctx.level >= 2 && verb.participle ? ['perfect'] : []),
+				...(ctx.level >= 3 ? ['past'] : [])
+			];
+			const tense = pick(ctx.rng, tenses);
+			const answer =
+				tense === 'present'
+					? present(verb, person)
+					: tense === 'past'
+						? person.plural
+							? [verb.past[1]]
+							: verb.past[0]
+						: perfect(verb, person);
+			const label = { present: 'present', perfect: 'perfect (heb/ben + ge-)', past: 'simple past' }[
+				tense
+			];
+			const wrong =
+				tense === 'perfect'
+					? [
+							`${AUX.h[person.slot]} ge${verb.ik}d`,
+							`${AUX.z[person.slot]} ${verb.participle}`,
+							`${AUX.h[person.slot]} ge${verb.ik}t`,
+							`${AUX.h[person.slot]} ${verb.inf}`
+						]
+					: mistakes(verb);
+			return ask(ctx, {
+				skill: `verbs-${tense}`,
+				instruction: `Conjugate · ${label}`,
+				prompt: `${person.label} · ${verb.inf}`,
+				promptLang: 'target',
+				context: verb.gloss,
+				answer,
+				wrong,
+				explain:
+					tense === 'past' && !verb.past[0][0].match(/[dt]e$/)
+						? `${verb.inf} is a strong verb: its past changes the vowel.`
+						: tense === 'present' && person.label === 'jij'
+							? 'Jij adds -t, except when inverted: "werk jij?".'
+							: undefined
+			});
+		}
+	}
+];

src/lib/language-learner/drills/shared.ts

@@ -0,0 +1,67 @@
+import { shuffle, type Rng } from '../random';
+import { optionKey } from '../text';
+import type { Course, Exercise } from '../types';
+import type { ExerciseOptions } from '../exercises';
+
+export type DrillContext = { rng: Rng; level: number; opts: ExerciseOptions; course: Course };
+
+export type DrillMode = {
+	id: string;
+	title: string;
+	description: string;
+	make: (ctx: DrillContext) => Exercise;
+};
+
+type Question = {
+	skill: string;
+	instruction: string;
+	prompt: string;
+	promptLang?: 'target' | 'gloss';
+	context?: string;
+	/** Accepted answers; the first is shown as the correct one. */
+	answer: string[];
+	wrong: string[];
+	explain?: string;
+	audio?: string;
+	/** Force multiple choice, e.g. for binary questions like de/het. */
+	choice?: boolean;
+};
+
+/** A typed question when typing is on, otherwise multiple choice with the given wrong answers. */
+export function ask(ctx: DrillContext, q: Question): Exercise {
+	const key = `${q.skill}:${q.prompt}`;
+	const base = {
+		key,
+		skill: q.skill,
+		instruction: q.instruction,
+		prompt: q.prompt,
+		promptLang: q.promptLang ?? ('gloss' as const),
+		context: q.context,
+		entries: [],
+		explain: q.explain,
+		audio: q.audio
+	};
+	if (ctx.opts.typing && !q.choice)
+		return { ...base, type: 'type', accept: q.answer, answerLang: 'target' };
+	const taken = new Set(q.answer.map(optionKey));
+	const wrong: string[] = [];
+	for (const w of q.wrong) {
+		if (taken.has(optionKey(w))) continue;
+		taken.add(optionKey(w));
+		wrong.push(w);
+		if (wrong.length === 3) break;
+	}
+	return {
+		...base,
+		type: 'choose',
+		options: shuffle(ctx.rng, [q.answer[0], ...wrong]),
+		answer: q.answer[0],
+		optionLang: 'target'
+	};
+}
+
+/** Accept "세 명" and "세명" alike. */
+export const withAndWithoutSpaces = (answers: string[]) => [
+	...answers,
+	...answers.map((a) => a.replace(/ /g, '')).filter((a) => !answers.includes(a))
+];

src/lib/language-learner/exercises.ts

@@ -0,0 +1,319 @@
+import { isSyllable } from './hangul';
+import { pick, sample, shuffle, type Rng } from './random';
+import { normalize, tiles } from './text';
+import type {
+	BuildExercise,
+	ChooseExercise,
+	Course,
+	Drill,
+	Entry,
+	Exercise,
+	Lesson,
+	MatchExercise,
+	TypeExercise
+} from './types';
+
+export type ExerciseOptions = {
+	/** Allow exercises that need a keyboard for the target language. */
+	typing: boolean;
+	/** Speech synthesis is available for the target language. */
+	audio: boolean;
+};
+
+const shown = (values: string[]) => values.join(' / ');
+
+const overlaps = (a: string[], b: string[]) => {
+	const set = new Set(a.map(normalize));
+	return b.some((value) => set.has(normalize(value)));
+};
+
+/** Plausible wrong answers: same kind, preferring the same lesson, never sharing an accepted answer. */
+function distractors(
+	entry: Entry,
+	pool: Entry[],
+	side: 'target' | 'gloss',
+	rng: Rng,
+	count = 3
+): string[] {
+	const candidates = pool.filter(
+		(other) =>
+			other.id !== entry.id && other.kind === entry.kind && !overlaps(other[side], entry[side])
+	);
+	const near = candidates.filter((other) => other.lesson === entry.lesson);
+	const values = (list: Entry[]) => list.map((other) => shown(other[side]));
+	const exclude = [shown(entry[side])];
+	const first = sample(rng, values(near), count, String, exclude);
+	return [
+		...first,
+		...sample(rng, values(candidates), count - first.length, String, [...exclude, ...first])
+	];
+}
+
+export function recognize(
+	entry: Entry,
+	pool: Entry[],
+	rng: Rng,
+	opts: ExerciseOptions
+): ChooseExercise {
+	const answer = shown(entry.gloss);
+	const listen = opts.audio && entry.kind !== 'script' && rng() < 0.2;
+	return {
+		key: `recognize:${entry.id}`,
+		type: 'choose',
+		instruction: listen
+			? 'What do you hear?'
+			: entry.kind === 'script'
+				? 'How is this read?'
+				: 'What does this mean?',
+		prompt: entry.target[0],
+		promptLang: 'target',
+		options: shuffle(rng, [answer, ...distractors(entry, pool, 'gloss', rng)]),
+		answer,
+		optionLang: 'gloss',
+		entries: [entry],
+		audio: speakable(entry) ? entry.target[0] : undefined,
+		listen,
+		explain: entry.note
+	};
+}
+
+export function produce(entry: Entry, pool: Entry[], rng: Rng): ChooseExercise {
+	const answer = shown(entry.target);
+	return {
+		key: `produce:${entry.id}`,
+		type: 'choose',
+		instruction: entry.kind === 'script' ? 'Which one is it?' : 'How do you say this?',
+		prompt: shown(entry.gloss),
+		promptLang: 'gloss',
+		options: shuffle(rng, [answer, ...distractors(entry, pool, 'target', rng)]),
+		answer,
+		optionLang: 'target',
+		entries: [entry],
+		audio: speakable(entry) ? entry.target[0] : undefined,
+		explain: entry.note
+	};
+}
+
+export function typeIt(entry: Entry): TypeExercise {
+	if (entry.kind === 'script')
+		return {
+			key: `type:${entry.id}`,
+			type: 'type',
+			instruction: 'Type the romanization',
+			prompt: entry.target[0],
+			promptLang: 'target',
+			accept: entry.gloss,
+			answerLang: 'gloss',
+			entries: [entry],
+			explain: entry.note
+		};
+	return {
+		key: `type:${entry.id}`,
+		type: 'type',
+		instruction: entry.kind === 'sentence' ? 'Translate this sentence' : 'Type the translation',
+		prompt: shown(entry.gloss),
+		promptLang: 'gloss',
+		accept: entry.target,
+		answerLang: 'target',
+		entries: [entry],
+		audio: entry.target[0],
+		explain: entry.note
+	};
+}
+
+export function dictation(entry: Entry): TypeExercise {
+	return {
+		key: `dictation:${entry.id}`,
+		type: 'type',
+		instruction: 'Type what you hear',
+		prompt: entry.target[0],
+		promptLang: 'target',
+		context: shown(entry.gloss),
+		accept: entry.target,
+		answerLang: 'target',
+		entries: [entry],
+		audio: entry.target[0],
+		listen: true
+	};
+}
+
+export function build(entry: Entry, pool: Entry[], rng: Rng): BuildExercise {
+	const answer = entry.target[0];
+	const own = tiles(answer);
+	const ownKeys = new Set(own.map(normalize));
+	const spare = pool
+		.filter((other) => other.kind === 'sentence' && other.id !== entry.id)
+		.flatMap((other) => tiles(other.target[0]))
+		.filter((tile) => !ownKeys.has(normalize(tile)));
+	const extra = sample(rng, spare, own.length > 6 ? 2 : 3, normalize);
+	return {
+		key: `build:${entry.id}`,
+		type: 'build',
+		instruction: 'Build the sentence',
+		prompt: shown(entry.gloss),
+		answer,
+		tiles: shuffle(rng, [...own, ...extra]),
+		entries: [entry],
+		audio: answer,
+		explain: entry.note
+	};
+}
+
+/** Blank out one word of a sentence, preferring a word the course teaches. */
+export function cloze(entry: Entry, pool: Entry[], rng: Rng): ChooseExercise | null {
+	const words = tiles(entry.target[0]);
+	if (words.length < 3) return null;
+	const taught = new Set(
+		pool
+			.filter((e) => e.kind === 'word')
+			.flatMap((e) => e.target.flatMap((t) => [normalize(t), normalize(t.split(' ').at(-1)!)]))
+	);
+	const indexes = words.map((_, i) => i).filter((i) => normalize(words[i]).length > 1);
+	if (!indexes.length) return null;
+	const preferred = indexes.filter((i) => taught.has(normalize(words[i])));
+	const index = pick(rng, preferred.length ? preferred : indexes);
+	const answer = normalize(words[index]);
+	const spare = pool
+		.filter((other) => other.kind === 'sentence' && other.id !== entry.id)
+		.flatMap((other) => tiles(other.target[0]).map(normalize))
+		.filter(
+			(word) =>
+				word.length > 1 &&
+				!entry.target.some((t) => normalize(t) === normalize(words.with(index, word).join(' ')))
+		);
+	const wrong = sample(rng, spare, 3, String, [answer]);
+	if (wrong.length < 2) return null;
+	const trailing = words[index].match(/[.,!?;:…]+$/)?.[0] ?? '';
+	return {
+		key: `cloze:${entry.id}`,
+		type: 'choose',
+		instruction: 'Fill in the blank',
+		prompt: words.with(index, '___' + trailing).join(' '),
+		promptLang: 'target',
+		context: shown(entry.gloss),
+		options: shuffle(rng, [answer, ...wrong]),
+		answer,
+		optionLang: 'target',
+		entries: [entry],
+		audio: entry.target[0],
+		explain: entry.note
+	};
+}
+
+/** Words to pair up; entries sharing a translation or spelling are left out so every pair is unambiguous. */
+export function match(candidates: Entry[], rng: Rng, count = 5): MatchExercise {
+	const entries: Entry[] = [];
+	for (const e of shuffle(rng, candidates)) {
+		if (entries.length === count) break;
+		const clash = entries.some(
+			(x) =>
+				normalize(x.gloss[0]) === normalize(e.gloss[0]) ||
+				normalize(x.target[0]) === normalize(e.target[0])
+		);
+		if (!clash) entries.push(e);
+	}
+	return {
+		key: `match:${entries.map((e) => e.id).join(',')}`,
+		type: 'match',
+		instruction: 'Match the pairs',
+		pairs: shuffle(rng, entries).map((e) => ({ target: e.target[0], gloss: e.gloss[0] })),
+		entries
+	};
+}
+
+export function fromDrill(drill: Drill, lessonId: string, rng: Rng): ChooseExercise {
+	return {
+		key: `drill:${lessonId}:${drill.prompt}`,
+		type: 'choose',
+		instruction: 'Choose the right answer',
+		prompt: drill.prompt,
+		promptLang: 'target',
+		options: shuffle(rng, [drill.answer, ...drill.wrong]),
+		answer: drill.answer,
+		optionLang: 'target',
+		entries: [],
+		explain: drill.explain
+	};
+}
+
+/** Script letters on their own are read by their name, not their sound, so skip audio for them. */
+const speakable = (entry: Entry) =>
+	entry.kind !== 'script' || [...entry.target[0]].every(isSyllable);
+
+/** A lesson run: meet every word, then mixed practice with sentences and grammar questions. */
+export function lessonSession(
+	course: Course,
+	lesson: Lesson,
+	rng: Rng,
+	opts: ExerciseOptions
+): Exercise[] {
+	const pool = coursePool(course, lesson.level);
+	const words = lesson.words;
+	const intro = words.map((w) => recognize(w, pool, rng, { ...opts, audio: false }));
+	const practice: Exercise[] = [];
+	for (const w of shuffle(rng, words).slice(0, Math.ceil(words.length / 2)))
+		practice.push(produce(w, pool, rng));
+	if (opts.typing || words.some((w) => w.kind === 'script'))
+		for (const w of sample(rng, words, 3, (w) => w.id))
+			if (opts.typing || w.kind === 'script') practice.push(typeIt(w));
+	if (opts.audio)
+		for (const w of sample(rng, words.filter(speakable), 2, (w) => w.id))
+			practice.push({
+				...recognize(w, pool, rng, opts),
+				listen: true,
+				instruction: 'What do you hear?',
+				key: `listen:${w.id}`
+			});
+	if (words.length >= 4) practice.push(match(words, rng));
+	const sentences = sample(rng, lesson.sentences, 5, (s) => s.id);
+	for (const s of sentences) practice.push(build(s, pool, rng));
+	for (const s of sample(rng, lesson.sentences, 2, (s) => s.id)) {
+		const c = cloze(s, pool, rng);
+		if (c) practice.push(c);
+	}
+	if (opts.audio && lesson.sentences.length)
+		practice.push(dictationOrListen(pick(rng, lesson.sentences), pool, rng, opts));
+	const grammar = sample(rng, lesson.drills, 6, (d) => d.prompt).map((d) =>
+		fromDrill(d, lesson.id, rng)
+	);
+	const rest = shuffle(rng, practice).slice(0, Math.max(6, 20 - intro.length - grammar.length));
+	return [...intro, ...shuffle(rng, [...rest, ...grammar])];
+}
+
+function dictationOrListen(entry: Entry, pool: Entry[], rng: Rng, opts: ExerciseOptions): Exercise {
+	if (opts.typing) return dictation(entry);
+	return {
+		...recognize(entry, pool, rng, opts),
+		listen: true,
+		instruction: 'What do you hear?',
+		key: `listen:${entry.id}`
+	};
+}
+
+/** One exercise for an entry, harder the better it is known (0 = new, 1 = well known). */
+export function reviewExercise(
+	entry: Entry,
+	pool: Entry[],
+	rng: Rng,
+	opts: ExerciseOptions,
+	strength = 0.5
+): Exercise {
+	const roll = rng() * 0.6 + strength * 0.4;
+	if (entry.kind === 'sentence') {
+		if (roll > 0.75 && opts.typing && tiles(entry.target[0]).length <= 5) return typeIt(entry);
+		if (roll > 0.55 && opts.audio) return dictationOrListen(entry, pool, rng, opts);
+		if (roll > 0.35) return cloze(entry, pool, rng) ?? build(entry, pool, rng);
+		return build(entry, pool, rng);
+	}
+	if (roll > 0.6 && (opts.typing || entry.kind === 'script')) return typeIt(entry);
+	if (roll > 0.4) return produce(entry, pool, rng);
+	return recognize(entry, pool, rng, opts);
+}
+
+/** Entries a lesson's distractors can come from: its level and the ones around it. */
+export function coursePool(course: Course, levelId: string): Entry[] {
+	const index = course.levels.findIndex((lv) => lv.id === levelId);
+	return course.levels
+		.filter((_, i) => Math.abs(i - index) <= 1)
+		.flatMap((lv) => lv.lessons.flatMap((ls) => [...ls.words, ...ls.sentences]));
+}

src/lib/language-learner/hangul.test.ts

@@ -0,0 +1,40 @@
+import { describe, expect, it } from 'vitest';
+import { compose, decompose, particle, romanize } from './hangul';
+
+describe('hangul', () => {
+	it('composes and decomposes syllables', () => {
+		expect(decompose('한')).toEqual({ initial: 'ㅎ', medial: 'ㅏ', final: 'ㄴ' });
+		expect(compose({ initial: 'ㄱ', medial: 'ㅡ', final: 'ㄹ' })).toBe('글');
+	});
+
+	it.each([
+		['안녕하세요', 'annyeonghaseyo'],
+		['감사합니다', 'gamsahamnida'],
+		['한국어', 'hangugeo'],
+		['맛있어요', 'masisseoyo'],
+		['읽어요', 'ilgeoyo'],
+		['많이', 'mani'],
+		['괜찮아요', 'gwaenchanayo'],
+		['없어요', 'eopseoyo'],
+		['같이', 'gachi'],
+		['좋다', 'jota'],
+		['신라', 'silla'],
+		['설날', 'seollal'],
+		['종로', 'jongno'],
+		['라면', 'ramyeon'],
+		['서울 사람', 'seoul saram'],
+		['의사', 'uisa']
+	])('romanizes %s as %s', (hangul, roman) => {
+		expect(romanize(hangul)).toBe(roman);
+	});
+
+	it('chooses particles by the final consonant', () => {
+		expect(particle('책', 'object')).toBe('책을');
+		expect(particle('사과', 'object')).toBe('사과를');
+		expect(particle('학생', 'topic')).toBe('학생은');
+		expect(particle('저', 'topic')).toBe('저는');
+		expect(particle('서울', 'direction')).toBe('서울로');
+		expect(particle('집', 'direction')).toBe('집으로');
+		expect(particle('의사', 'copula')).toBe('의사예요');
+	});
+});

src/lib/language-learner/hangul.ts

@@ -0,0 +1,217 @@
+/** Hangul composition, approximate Revised Romanization and particle choice. */
+
+export const INITIALS = [...'ㄱㄲㄴㄷㄸㄹㅁㅂㅃㅅㅆㅇㅈㅉㅊㅋㅌㅍㅎ'];
+export const MEDIALS = [...'ㅏㅐㅑㅒㅓㅔㅕㅖㅗㅘㅙㅚㅛㅜㅝㅞㅟㅠㅡㅢㅣ'];
+export const FINALS = ['', ...'ㄱㄲㄳㄴㄵㄶㄷㄹㄺㄻㄼㄽㄾㄿㅀㅁㅂㅄㅅㅆㅇㅈㅊㅋㅌㅍㅎ'];
+
+const BASE = 0xac00;
+
+export type Syllable = { initial: string; medial: string; final: string };
+
+export function isSyllable(char: string | undefined): boolean {
+	if (!char) return false;
+	const code = char.charCodeAt(0);
+	return code >= BASE && code <= 0xd7a3;
+}
+
+export function decompose(char: string): Syllable | null {
+	if (!isSyllable(char)) return null;
+	const offset = char.charCodeAt(0) - BASE;
+	return {
+		initial: INITIALS[Math.floor(offset / 588)],
+		medial: MEDIALS[Math.floor((offset % 588) / 28)],
+		final: FINALS[offset % 28]
+	};
+}
+
+export function compose({ initial, medial, final }: Syllable): string {
+	const i = INITIALS.indexOf(initial);
+	const m = MEDIALS.indexOf(medial);
+	const f = FINALS.indexOf(final);
+	if (i < 0 || m < 0 || f < 0) throw new Error(`Cannot compose ${initial}${medial}${final}`);
+	return String.fromCharCode(BASE + (i * 21 + m) * 28 + f);
+}
+
+/** Replace the final consonant of the last syllable of `word`. */
+export function withFinal(word: string, final: string): string {
+	const last = decompose(word.at(-1)!);
+	if (!last) throw new Error(`Not Hangul: ${word}`);
+	return word.slice(0, -1) + compose({ ...last, final });
+}
+
+export function lastSyllable(word: string): Syllable | null {
+	const chars = [...word.replace(/[^가-힣]+$/u, '')];
+	return chars.length ? decompose(chars.at(-1)!) : null;
+}
+
+export const hasBatchim = (word: string) => !!lastSyllable(word)?.final;
+
+const ROMAN_INITIAL: Record<string, string> = {
+	ㄱ: 'g',
+	ㄲ: 'kk',
+	ㄴ: 'n',
+	ㄷ: 'd',
+	ㄸ: 'tt',
+	ㄹ: 'r',
+	ㅁ: 'm',
+	ㅂ: 'b',
+	ㅃ: 'pp',
+	ㅅ: 's',
+	ㅆ: 'ss',
+	ㅇ: '',
+	ㅈ: 'j',
+	ㅉ: 'jj',
+	ㅊ: 'ch',
+	ㅋ: 'k',
+	ㅌ: 't',
+	ㅍ: 'p',
+	ㅎ: 'h'
+};
+const ROMAN_MEDIAL: Record<string, string> = {
+	ㅏ: 'a',
+	ㅐ: 'ae',
+	ㅑ: 'ya',
+	ㅒ: 'yae',
+	ㅓ: 'eo',
+	ㅔ: 'e',
+	ㅕ: 'yeo',
+	ㅖ: 'ye',
+	ㅗ: 'o',
+	ㅘ: 'wa',
+	ㅙ: 'wae',
+	ㅚ: 'oe',
+	ㅛ: 'yo',
+	ㅜ: 'u',
+	ㅝ: 'wo',
+	ㅞ: 'we',
+	ㅟ: 'wi',
+	ㅠ: 'yu',
+	ㅡ: 'eu',
+	ㅢ: 'ui',
+	ㅣ: 'i'
+};
+/** The sound a final consonant makes before a pause, as one of k/n/t/l/m/p/ng. */
+const FINAL_SOUND: Record<string, string> = {
+	ㄱ: 'k',
+	ㄲ: 'k',
+	ㄳ: 'k',
+	ㄺ: 'k',
+	ㅋ: 'k',
+	ㄴ: 'n',
+	ㄵ: 'n',
+	ㄶ: 'n',
+	ㄷ: 't',
+	ㅅ: 't',
+	ㅆ: 't',
+	ㅈ: 't',
+	ㅊ: 't',
+	ㅌ: 't',
+	ㅎ: 't',
+	ㄹ: 'l',
+	ㄼ: 'l',
+	ㄽ: 'l',
+	ㄾ: 'l',
+	ㅀ: 'l',
+	ㅁ: 'm',
+	ㄻ: 'm',
+	ㅂ: 'p',
+	ㅄ: 'p',
+	ㄿ: 'p',
+	ㅍ: 'p',
+	ㅇ: 'ng'
+};
+/** Compound finals split into the part that stays and the part that moves on. */
+const SPLIT: Record<string, [string, string]> = {
+	ㄳ: ['ㄱ', 'ㅅ'],
+	ㄵ: ['ㄴ', 'ㅈ'],
+	ㄶ: ['', 'ㄴ'],
+	ㄺ: ['ㄹ', 'ㄱ'],
+	ㄻ: ['ㄹ', 'ㅁ'],
+	ㄼ: ['ㄹ', 'ㅂ'],
+	ㄽ: ['ㄹ', 'ㅅ'],
+	ㄾ: ['ㄹ', 'ㅌ'],
+	ㄿ: ['ㄹ', 'ㅍ'],
+	ㅀ: ['', 'ㄹ'],
+	ㅄ: ['ㅂ', 'ㅅ']
+};
+const ASPIRATED: Record<string, string> = {
+	k: 'ㅋ',
+	t: 'ㅌ',
+	p: 'ㅍ',
+	ㄱ: 'ㅋ',
+	ㄷ: 'ㅌ',
+	ㅈ: 'ㅊ'
+};
+const NASAL: Record<string, string> = { k: 'ㅇ', t: 'ㄴ', p: 'ㅁ' };
+
+function romanizeWord(chars: Syllable[]): string {
+	const s = chars.map((c) => ({ ...c }));
+	for (let j = 0; j < s.length - 1; j++) {
+		const a = s[j];
+		const b = s[j + 1];
+		const f = a.final;
+		if (!f) continue;
+		const sound = FINAL_SOUND[f];
+		if (b.initial === 'ㅇ') {
+			if (f === 'ㅇ') continue;
+			if (f === 'ㅎ') a.final = '';
+			else if (SPLIT[f]) [a.final, b.initial] = SPLIT[f];
+			else [a.final, b.initial] = ['', f];
+			// palatalization: 같이 → gachi, 굳이 → guji
+			if (b.medial === 'ㅣ' && (b.initial === 'ㄷ' || b.initial === 'ㅌ'))
+				b.initial = b.initial === 'ㄷ' ? 'ㅈ' : 'ㅊ';
+		} else if ((f === 'ㅎ' || f === 'ㄶ' || f === 'ㅀ') && ASPIRATED[b.initial]) {
+			a.final = f === 'ㅎ' ? '' : f === 'ㄶ' ? 'ㄴ' : 'ㄹ';
+			b.initial = ASPIRATED[b.initial];
+		} else if (b.initial === 'ㅎ' && NASAL[sound]) {
+			a.final = SPLIT[f]?.[0] ?? '';
+			b.initial = ASPIRATED[sound];
+		} else if (NASAL[sound] && (b.initial === 'ㄴ' || b.initial === 'ㅁ')) {
+			a.final = NASAL[sound];
+		} else if (NASAL[sound] && b.initial === 'ㄹ') {
+			a.final = NASAL[sound];
+			b.initial = 'ㄴ';
+		} else if (sound === 'n' && b.initial === 'ㄹ') {
+			a.final = 'ㄹ';
+		} else if (sound === 'l' && b.initial === 'ㄴ') {
+			b.initial = 'ㄹ';
+		} else if ((sound === 'm' || sound === 'ng') && b.initial === 'ㄹ') {
+			b.initial = 'ㄴ';
+		}
+	}
+	return s
+		.map((c, j) => {
+			const initial =
+				c.initial === 'ㄹ' && j > 0 && FINAL_SOUND[s[j - 1].final] === 'l'
+					? 'l'
+					: ROMAN_INITIAL[c.initial];
+			return initial + ROMAN_MEDIAL[c.medial] + (c.final ? FINAL_SOUND[c.final] : '');
+		})
+		.join('');
+}
+
+/** Approximate Revised Romanization, including the common sound changes between syllables. */
+export function romanize(text: string): string {
+	return text.replace(/[가-힣]+/gu, (word) =>
+		romanizeWord([...word].map((char) => decompose(char)!))
+	);
+}
+
+export type Particle = 'topic' | 'subject' | 'object' | 'and' | 'with' | 'direction' | 'copula';
+
+/** Attach a particle, choosing the form by whether the noun ends in a consonant. */
+export function particle(noun: string, kind: Particle): string {
+	const last = lastSyllable(noun);
+	const batchim = !!last?.final;
+	const forms: Record<Particle, [string, string]> = {
+		topic: ['은', '는'],
+		subject: ['이', '가'],
+		object: ['을', '를'],
+		and: ['과', '와'],
+		with: ['이랑', '랑'],
+		direction: ['으로', '로'],
+		copula: ['이에요', '예요']
+	};
+	if (kind === 'direction' && last?.final === 'ㄹ') return noun + '로';
+	return noun + forms[kind][batchim ? 0 : 1];
+}

src/lib/language-learner/korean-verbs.test.ts

@@ -0,0 +1,77 @@
+import { describe, expect, it } from 'vitest';
+import { conjugate, KOREAN_VERBS, type KoreanForm } from './korean-verbs';
+
+const verb = (dict: string) => {
+	const found = KOREAN_VERBS.find((v) => v.dict === dict);
+	if (!found) throw new Error(dict);
+	return found;
+};
+const form = (dict: string, f: KoreanForm) => conjugate(verb(dict), f)[0];
+
+describe('korean conjugation', () => {
+	it.each([
+		['가다', '가요', '갔어요'],
+		['오다', '와요', '왔어요'],
+		['먹다', '먹어요', '먹었어요'],
+		['마시다', '마셔요', '마셨어요'],
+		['보다', '봐요', '봤어요'],
+		['하다', '해요', '했어요'],
+		['공부하다', '공부해요', '공부했어요'],
+		['배우다', '배워요', '배웠어요'],
+		['쓰다', '써요', '썼어요'],
+		['바쁘다', '바빠요', '바빴어요'],
+		['크다', '커요', '컸어요'],
+		['되다', '돼요', '됐어요'],
+		['보내다', '보내요', '보냈어요'],
+		['쉬다', '쉬어요', '쉬었어요'],
+		['듣다', '들어요', '들었어요'],
+		['돕다', '도와요', '도왔어요'],
+		['춥다', '추워요', '추웠어요'],
+		['모르다', '몰라요', '몰랐어요'],
+		['부르다', '불러요', '불렀어요'],
+		['낫다', '나아요', '나았어요'],
+		['짓다', '지어요', '지었어요'],
+		['그렇다', '그래요', '그랬어요'],
+		['하얗다', '하얘요', '하얬어요'],
+		['좋다', '좋아요', '좋았어요'],
+		['받다', '받아요', '받았어요'],
+		['웃다', '웃어요', '웃었어요'],
+		['살다', '살아요', '살았어요'],
+		['기다리다', '기다려요', '기다렸어요'],
+		['춤추다', '춤춰요', '춤췄어요'],
+		['빠르다', '빨라요', '빨랐어요']
+	])('%s → %s / %s', (dict, present, past) => {
+		expect(form(dict, 'present')).toBe(present);
+		expect(form(dict, 'past')).toBe(past);
+	});
+
+	it('builds future, formal, request and negative forms', () => {
+		expect(form('가다', 'future')).toBe('갈 거예요');
+		expect(form('먹다', 'future')).toBe('먹을 거예요');
+		expect(form('살다', 'future')).toBe('살 거예요');
+		expect(form('춥다', 'future')).toBe('추울 거예요');
+		expect(form('듣다', 'future')).toBe('들을 거예요');
+		expect(form('그렇다', 'future')).toBe('그럴 거예요');
+		expect(form('가다', 'formal')).toBe('갑니다');
+		expect(form('먹다', 'formal')).toBe('먹습니다');
+		expect(form('살다', 'formal')).toBe('삽니다');
+		expect(form('만들다', 'formal')).toBe('만듭니다');
+		expect(form('읽다', 'request')).toBe('읽으세요');
+		expect(form('앉다', 'request')).toBe('앉으세요');
+		expect(form('만들다', 'request')).toBe('만드세요');
+		expect(form('돕다', 'request')).toBe('도우세요');
+		expect(form('듣다', 'request')).toBe('들으세요');
+		expect(form('먹다', 'request')).toBe('드세요');
+		expect(form('공부하다', 'negative')).toBe('공부 안 해요');
+		expect(conjugate(verb('가다'), 'negative')).toEqual(['안 가요', '가지 않아요']);
+		expect(form('있다', 'negative')).toBe('없어요');
+		expect(form('듣다', 'can')).toBe('들을 수 있어요');
+		expect(form('보다', 'want')).toBe('보고 싶어요');
+	});
+
+	it('conjugates every listed verb without throwing', () => {
+		for (const v of KOREAN_VERBS)
+			for (const f of ['present', 'past', 'future', 'formal', 'request', 'negative'] as const)
+				expect(conjugate(v, f)[0]).toMatch(/[가-힣]/);
+	});
+});

src/lib/language-learner/korean-verbs.ts

@@ -0,0 +1,343 @@
+import { compose, decompose, lastSyllable, withFinal } from './hangul';
+
+/** Irregular classes: ㅂ, ㄷ, 르, ㅅ and ㅎ. ㄹ-dropping and 으-dropping are handled as regular rules. */
+export type Irregular = 'b' | 'd' | 'reu' | 's' | 'h';
+
+export type KoreanVerb = {
+	dict: string;
+	gloss: string;
+	/** Action verbs take -고 싶어요, -고 있어요 and -(으)세요; descriptive verbs do not. */
+	action: boolean;
+	irr?: Irregular;
+	/** Noun + 하다 verbs, which negate as 공부 안 해요 rather than 안 공부해요. */
+	noun?: boolean;
+	level: number;
+};
+
+const replaceLast = (word: string, next: string) => word.slice(0, -1) + next;
+
+const bright = (medial: string) => medial === 'ㅏ' || medial === 'ㅗ' || medial === 'ㅑ';
+
+/** The 아/어 form (casual present), the base for polite present and past. */
+export function infinitive(verb: Pick<KoreanVerb, 'dict' | 'irr'>): string {
+	const stem = verb.dict.slice(0, -1);
+	if (stem.endsWith('하')) return replaceLast(stem, '해');
+	const last = decompose(stem.at(-1)!)!;
+	const previous = stem.length > 1 ? decompose(stem.at(-2)!) : null;
+
+	if (verb.irr === 'b' && last.final === 'ㅂ') {
+		const base = replaceLast(stem, compose({ ...last, final: '' }));
+		return base + (stem === '돕' || stem === '곱' ? '와' : '워');
+	}
+	if (verb.irr === 'd' && last.final === 'ㄷ')
+		return withFinal(stem, 'ㄹ') + (bright(last.medial) ? '아' : '어');
+	if (verb.irr === 's' && last.final === 'ㅅ')
+		return withFinal(stem, '') + (bright(last.medial) ? '아' : '어');
+	if (verb.irr === 'reu' && stem.endsWith('르') && previous) {
+		const head = stem.slice(0, -2) + compose({ ...previous, final: 'ㄹ' });
+		return head + (bright(previous.medial) ? '라' : '러');
+	}
+	if (verb.irr === 'h' && last.final === 'ㅎ')
+		return replaceLast(
+			stem,
+			compose({ ...last, medial: last.medial === 'ㅑ' ? 'ㅒ' : 'ㅐ', final: '' })
+		);
+
+	if (last.final) return stem + (bright(last.medial) ? '아' : '어');
+
+	const contracted: Record<string, string> = { ㅗ: 'ㅘ', ㅜ: 'ㅝ', ㅣ: 'ㅕ', ㅚ: 'ㅙ' };
+	switch (last.medial) {
+		case 'ㅏ':
+		case 'ㅓ':
+		case 'ㅐ':
+		case 'ㅔ':
+		case 'ㅕ':
+			return stem;
+		case 'ㅡ': {
+			const vowel = previous && bright(previous.medial) ? 'ㅏ' : 'ㅓ';
+			return replaceLast(stem, compose({ ...last, medial: vowel }));
+		}
+		default:
+			if (contracted[last.medial])
+				return replaceLast(stem, compose({ ...last, medial: contracted[last.medial] }));
+			return stem + '어';
+	}
+}
+
+/** The stem with (으)ㄹ attached, used for the future and for "can". */
+export function futureStem(verb: Pick<KoreanVerb, 'dict' | 'irr'>): string {
+	const stem = verb.dict.slice(0, -1);
+	const last = lastSyllable(stem)!;
+	if (last.final === 'ㄹ') return stem;
+	if (verb.irr === 'b' && last.final === 'ㅂ') return withFinal(stem, '') + '울';
+	if (verb.irr === 'd' && last.final === 'ㄷ') return withFinal(stem, 'ㄹ') + '을';
+	if (verb.irr === 's' && last.final === 'ㅅ') return withFinal(stem, '') + '을';
+	if (verb.irr === 'h' && last.final === 'ㅎ') return withFinal(stem, 'ㄹ');
+	if (!last.final) return withFinal(stem, 'ㄹ');
+	return stem + '을';
+}
+
+const HONORIFIC: Record<string, string> = {
+	먹다: '드세요',
+	마시다: '드세요',
+	자다: '주무세요',
+	있다: '계세요',
+	말하다: '말씀하세요'
+};
+
+export type KoreanForm =
+	| 'present'
+	| 'past'
+	| 'future'
+	| 'formal'
+	| 'want'
+	| 'progressive'
+	| 'negative'
+	| 'can'
+	| 'request'
+	| 'casual';
+
+export const FORM_LABELS: Record<KoreanForm, string> = {
+	present: 'polite present (-아요/어요)',
+	past: 'polite past (-았어요/었어요)',
+	future: 'future (-(으)ㄹ 거예요)',
+	formal: 'formal (-(스)ㅂ니다)',
+	want: 'want to (-고 싶어요)',
+	progressive: 'is doing (-고 있어요)',
+	negative: 'negative (안 / -지 않아요)',
+	can: 'can (-(으)ㄹ 수 있어요)',
+	request: 'polite request (-(으)세요)',
+	casual: 'casual present (반말)'
+};
+
+export const ACTION_FORMS: KoreanForm[] = Object.keys(FORM_LABELS) as KoreanForm[];
+export const DESCRIPTIVE_FORMS: KoreanForm[] = [
+	'present',
+	'past',
+	'future',
+	'formal',
+	'negative',
+	'casual'
+];
+
+/** Every accepted answer for a form; the first one is the canonical answer. */
+export function conjugate(verb: KoreanVerb, form: KoreanForm): string[] {
+	const stem = verb.dict.slice(0, -1);
+	const inf = infinitive(verb);
+	const present = inf + '요';
+	switch (form) {
+		case 'present':
+			return [present];
+		case 'casual':
+			return [inf];
+		case 'past':
+			return [withFinal(inf, 'ㅆ') + '어요'];
+		case 'future':
+			return [futureStem(verb) + ' 거예요'];
+		case 'can':
+			return [futureStem(verb) + ' 수 있어요'];
+		case 'formal': {
+			const last = lastSyllable(stem)!;
+			if (last.final === 'ㄹ') return [withFinal(stem, 'ㅂ') + '니다'];
+			return [last.final ? stem + '습니다' : withFinal(stem, 'ㅂ') + '니다'];
+		}
+		case 'want':
+			return [stem + '고 싶어요'];
+		case 'progressive':
+			return [stem + '고 있어요'];
+		case 'request': {
+			if (HONORIFIC[verb.dict]) return [HONORIFIC[verb.dict]];
+			const last = lastSyllable(stem)!;
+			if (last.final === 'ㄹ') return [withFinal(stem, '') + '세요'];
+			if (verb.irr === 'b' && last.final === 'ㅂ') return [withFinal(stem, '') + '우세요'];
+			if (verb.irr === 'h' && last.final === 'ㅎ') return [withFinal(stem, '') + '세요'];
+			if (verb.irr === 'd' || verb.irr === 's') return [futureStem(verb).slice(0, -1) + '으세요'];
+			return [last.final ? stem + '으세요' : stem + '세요'];
+		}
+		case 'negative': {
+			const long = stem + '지 않아요';
+			if (verb.dict === '있다') return ['없어요', long];
+			if (verb.dict === '알다') return ['몰라요', long];
+			if (verb.dict === '맛있다') return ['맛없어요', long];
+			if (verb.dict === '재미있다') return ['재미없어요', long];
+			if (verb.noun) return [`${verb.dict.slice(0, -2)} 안 해요`, long];
+			return [`안 ${present}`, long];
+		}
+	}
+}
+
+const verbs = (level: number, action: boolean, source: string): KoreanVerb[] =>
+	source
+		.trim()
+		.split('\n')
+		.map((line) => {
+			const [dict, gloss, flags = ''] = line.split('|').map((part) => part.trim());
+			const irr = (['b', 'd', 'reu', 's', 'h'] as const).find((i) => flags.split(' ').includes(i));
+			// 'plain' marks action verbs that make no sense as a wish or a request (끝나다, 되다)
+			return {
+				dict,
+				gloss,
+				action: action && !flags.includes('plain'),
+				level,
+				irr,
+				noun: flags.includes('noun')
+			};
+		});
+
+export const KOREAN_VERBS: KoreanVerb[] = [
+	...verbs(
+		1,
+		true,
+		`
+가다|to go
+오다|to come
+먹다|to eat
+마시다|to drink
+보다|to see, to watch
+하다|to do
+자다|to sleep
+읽다|to read
+사다|to buy
+만나다|to meet
+공부하다|to study|noun
+일하다|to work|noun
+좋아하다|to like
+앉다|to sit
+배우다|to learn
+가르치다|to teach
+기다리다|to wait
+주다|to give
+쓰다|to write, to use
+살다|to live
+알다|to know
+만들다|to make
+타다|to ride, to take (transport)
+입다|to wear (clothes)
+받다|to receive
+닫다|to close
+열다|to open
+놀다|to play, to hang out
+있다|to be (somewhere), to have
+`
+	),
+	...verbs(
+		1,
+		false,
+		`
+좋다|to be good
+크다|to be big
+작다|to be small
+많다|to be many, a lot
+비싸다|to be expensive
+싸다|to be cheap
+맛있다|to be tasty
+재미있다|to be fun
+바쁘다|to be busy
+예쁘다|to be pretty
+괜찮다|to be okay
+`
+	),
+	...verbs(
+		2,
+		true,
+		`
+듣다|to listen|d
+걷다|to walk|d
+돕다|to help|b
+부르다|to sing, to call|reu
+모르다|to not know|reu
+씻다|to wash
+팔다|to sell
+울다|to cry
+웃다|to laugh, to smile
+보내다|to send
+끝나다|to end|plain
+시작하다|to start
+운동하다|to exercise|noun
+요리하다|to cook|noun
+전화하다|to phone|noun
+청소하다|to clean|noun
+쉬다|to rest
+찾다|to look for, to find
+빌리다|to borrow
+춤추다|to dance
+여행하다|to travel|noun
+되다|to become|plain
+찍다|to take (a photo)
+`
+	),
+	...verbs(
+		2,
+		false,
+		`
+덥다|to be hot (weather)|b
+춥다|to be cold (weather)|b
+어렵다|to be difficult|b
+쉽다|to be easy|b
+맵다|to be spicy|b
+가깝다|to be close|b
+멀다|to be far
+길다|to be long
+빠르다|to be fast|reu
+다르다|to be different|reu
+아프다|to hurt, to be sick
+슬프다|to be sad
+기쁘다|to be glad
+피곤하다|to be tired
+조용하다|to be quiet
+따뜻하다|to be warm
+높다|to be high
+나쁘다|to be bad
+`
+	),
+	...verbs(
+		3,
+		true,
+		`
+묻다|to ask|d
+짓다|to build, to make up (a name)|s
+붓다|to pour|s
+긋다|to draw (a line)|s
+자르다|to cut|reu
+고르다|to choose|reu
+서두르다|to hurry|reu
+누르다|to press|reu
+굽다|to grill, to bake|b
+눕다|to lie down|b
+깨닫다|to realize|d
+싣다|to load|d
+생각하다|to think
+이야기하다|to talk|noun
+준비하다|to prepare|noun
+결정하다|to decide
+설명하다|to explain
+잊어버리다|to forget
+싸우다|to fight
+`
+	),
+	...verbs(
+		3,
+		false,
+		`
+그렇다|to be like that|h
+이렇다|to be like this|h
+어떻다|to be how|h
+빨갛다|to be red|h
+파랗다|to be blue|h
+노랗다|to be yellow|h
+하얗다|to be white|h
+까맣다|to be black|h
+귀엽다|to be cute|b
+무겁다|to be heavy|b
+가볍다|to be light|b
+즐겁다|to be enjoyable|b
+부럽다|to be envious|b
+낫다|to be better|s
+넓다|to be wide
+좁다|to be narrow
+행복하다|to be happy
+시원하다|to be cool, refreshing
+게으르다|to be lazy|reu
+`
+	)
+];

src/lib/language-learner/modes.ts

@@ -0,0 +1,41 @@
+export type ModeId = 'daily' | 'sprint' | 'survival' | 'endless' | 'review';
+
+export type ModeInfo = {
+	id: ModeId;
+	title: string;
+	description: string;
+	group: 'challenge' | 'review';
+};
+
+export const MODES: ModeInfo[] = [
+	{
+		id: 'daily',
+		title: 'Daily challenge',
+		description: '20 questions, the same all day. Your first score counts.',
+		group: 'challenge'
+	},
+	{
+		id: 'sprint',
+		title: 'Sprint',
+		description: 'As many right answers as you can in 60 seconds.',
+		group: 'challenge'
+	},
+	{
+		id: 'survival',
+		title: 'Survival',
+		description: 'Endless and slowly harder. Three mistakes and you are out.',
+		group: 'challenge'
+	},
+	{
+		id: 'endless',
+		title: 'Mixed practice',
+		description: 'No timer, no lives. Words, grammar and drills until you stop.',
+		group: 'challenge'
+	},
+	{
+		id: 'review',
+		title: 'Review',
+		description: 'Spaced repetition: due words first, then your weakest ones.',
+		group: 'review'
+	}
+];

src/lib/language-learner/numbers.test.ts

@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest';
+import { dutchNumber, englishNumber, nativeKorean, sinoKorean } from './numbers';
+
+describe('number words', () => {
+	it('writes Dutch numbers', () => {
+		expect(dutchNumber(0)).toBe('nul');
+		expect(dutchNumber(21)).toBe('eenentwintig');
+		expect(dutchNumber(22)).toBe('tweeëntwintig');
+		expect(dutchNumber(83)).toBe('drieëntachtig');
+		expect(dutchNumber(100)).toBe('honderd');
+		expect(dutchNumber(345)).toBe('driehonderdvijfenveertig');
+		expect(dutchNumber(1998)).toBe('duizendnegenhonderdachtennegentig');
+		expect(dutchNumber(2026)).toBe('tweeduizendzesentwintig');
+		expect(dutchNumber(3_500_000)).toBe('drie miljoen vijfhonderdduizend');
+	});
+
+	it('writes English numbers', () => {
+		expect(englishNumber(42)).toBe('forty-two');
+		expect(englishNumber(105)).toBe('one hundred and five');
+		expect(englishNumber(2005)).toBe('two thousand and five');
+		expect(englishNumber(1250)).toBe('one thousand two hundred and fifty');
+	});
+
+	it('writes Korean numbers', () => {
+		expect(sinoKorean(10)).toBe('십');
+		expect(sinoKorean(16)).toBe('십육');
+		expect(sinoKorean(250)).toBe('이백오십');
+		expect(sinoKorean(10000)).toBe('만');
+		expect(sinoKorean(35000)).toBe('삼만오천');
+		expect(sinoKorean(2026)).toBe('이천이십육');
+		expect(nativeKorean(1)).toBe('하나');
+		expect(nativeKorean(24)).toBe('스물넷');
+		expect(nativeKorean(20, true)).toBe('스무');
+		expect(nativeKorean(23, true)).toBe('스물세');
+		expect(nativeKorean(4, true)).toBe('네');
+	});
+});

src/lib/language-learner/numbers.ts

@@ -0,0 +1,166 @@
+/** Number words, so number drills can generate endless questions. */
+
+const NL_UNITS = [
+	'nul',
+	'een',
+	'twee',
+	'drie',
+	'vier',
+	'vijf',
+	'zes',
+	'zeven',
+	'acht',
+	'negen',
+	'tien',
+	'elf',
+	'twaalf',
+	'dertien',
+	'veertien',
+	'vijftien',
+	'zestien',
+	'zeventien',
+	'achttien',
+	'negentien'
+];
+const NL_TENS = [
+	'',
+	'',
+	'twintig',
+	'dertig',
+	'veertig',
+	'vijftig',
+	'zestig',
+	'zeventig',
+	'tachtig',
+	'negentig'
+];
+
+function dutchBelowThousand(n: number): string {
+	if (n < 20) return NL_UNITS[n];
+	if (n < 100) {
+		const unit = n % 10;
+		const tens = NL_TENS[Math.floor(n / 10)];
+		if (!unit) return tens;
+		const word = NL_UNITS[unit];
+		// tweeëntwintig, drieëntwintig: a diaeresis separates the e's
+		return word + (word.endsWith('e') ? 'ën' : 'en') + tens;
+	}
+	const hundreds = Math.floor(n / 100);
+	const rest = n % 100;
+	return (
+		(hundreds === 1 ? '' : NL_UNITS[hundreds]) + 'honderd' + (rest ? dutchBelowThousand(rest) : '')
+	);
+}
+
+export function dutchNumber(n: number): string {
+	if (n < 1000) return dutchBelowThousand(n);
+	if (n < 1_000_000) {
+		const thousands = Math.floor(n / 1000);
+		const rest = n % 1000;
+		return (
+			(thousands === 1 ? '' : dutchBelowThousand(thousands)) +
+			'duizend' +
+			(rest ? dutchBelowThousand(rest) : '')
+		);
+	}
+	const millions = Math.floor(n / 1_000_000);
+	const rest = n % 1_000_000;
+	return `${dutchBelowThousand(millions)} miljoen${rest ? ' ' + dutchNumber(rest) : ''}`;
+}
+
+const EN_UNITS = [
+	'zero',
+	'one',
+	'two',
+	'three',
+	'four',
+	'five',
+	'six',
+	'seven',
+	'eight',
+	'nine',
+	'ten',
+	'eleven',
+	'twelve',
+	'thirteen',
+	'fourteen',
+	'fifteen',
+	'sixteen',
+	'seventeen',
+	'eighteen',
+	'nineteen'
+];
+const EN_TENS = [
+	'',
+	'',
+	'twenty',
+	'thirty',
+	'forty',
+	'fifty',
+	'sixty',
+	'seventy',
+	'eighty',
+	'ninety'
+];
+
+function englishBelowThousand(n: number): string {
+	if (n < 20) return EN_UNITS[n];
+	if (n < 100) return EN_TENS[Math.floor(n / 10)] + (n % 10 ? '-' + EN_UNITS[n % 10] : '');
+	const rest = n % 100;
+	return `${EN_UNITS[Math.floor(n / 100)]} hundred${rest ? ' and ' + englishBelowThousand(rest) : ''}`;
+}
+
+/** British style ("one hundred and five"); answers are also accepted without "and". */
+export function englishNumber(n: number): string {
+	if (n < 1000) return englishBelowThousand(n);
+	if (n < 1_000_000) {
+		const rest = n % 1000;
+		const joiner = rest && rest < 100 ? ' and ' : ' ';
+		return `${englishBelowThousand(Math.floor(n / 1000))} thousand${rest ? joiner + englishBelowThousand(rest) : ''}`;
+	}
+	const rest = n % 1_000_000;
+	return `${englishBelowThousand(Math.floor(n / 1_000_000))} million${rest ? ' ' + englishNumber(rest) : ''}`;
+}
+
+const SINO = ['', '일', '이', '삼', '사', '오', '육', '칠', '팔', '구'];
+
+function sinoBelowTenThousand(n: number): string {
+	const places: [number, string][] = [
+		[1000, '천'],
+		[100, '백'],
+		[10, '십']
+	];
+	let out = '';
+	for (const [value, name] of places) {
+		const digit = Math.floor(n / value) % 10;
+		if (digit) out += (digit === 1 ? '' : SINO[digit]) + name;
+	}
+	return out + SINO[n % 10];
+}
+
+/** Sino-Korean numbers: dates, money, minutes, phone numbers. 10,000 is 만. */
+export function sinoKorean(n: number): string {
+	if (n === 0) return '영';
+	const man = Math.floor(n / 10000);
+	const rest = n % 10000;
+	return (
+		(man ? (man === 1 ? '' : sinoBelowTenThousand(man)) + '만' : '') +
+		(rest ? sinoBelowTenThousand(rest) : '')
+	);
+}
+
+const NATIVE_UNITS = ['', '하나', '둘', '셋', '넷', '다섯', '여섯', '일곱', '여덟', '아홉'];
+const NATIVE_TENS = ['', '열', '스물', '서른', '마흔', '쉰', '예순', '일흔', '여든', '아흔'];
+const COUNTER_UNITS: Record<number, string> = { 1: '한', 2: '두', 3: '세', 4: '네' };
+
+/** Native Korean numbers (1–99): counting things, age, hours. `counter` uses 한/두/세/네/스무. */
+export function nativeKorean(n: number, counter = false): string {
+	if (n < 1 || n > 99) throw new RangeError('Native Korean numbers run from 1 to 99');
+	const tens = Math.floor(n / 10);
+	const unit = n % 10;
+	if (counter) {
+		if (n === 20) return '스무';
+		return NATIVE_TENS[tens] + (COUNTER_UNITS[unit] ?? NATIVE_UNITS[unit]);
+	}
+	return NATIVE_TENS[tens] + NATIVE_UNITS[unit];
+}

src/lib/language-learner/progress.svelte.ts

@@ -0,0 +1,194 @@
+import { browser } from '$app/environment';
+import { dayKey, dayNumber, newCard, review, type Card } from './srs';
+import type { Entry, LangCode } from './types';
+
+export type LessonRecord = { best: number; runs: number; last: string };
+
+export type LangProgress = {
+	lessons: Record<string, LessonRecord>;
+	cards: Record<string, Card>;
+	xp: number;
+	/** XP earned per local day, `YYYY-MM-DD`. */
+	days: Record<string, number>;
+	/** First daily-challenge score per day, as a percentage. */
+	daily: Record<string, number>;
+	/** Best score per challenge mode. */
+	bests: Record<string, number>;
+	/** Accuracy per endless drill. */
+	skills: Record<string, { seen: number; right: number }>;
+	/** Level last chosen for mixed challenges; empty means "what I have learned". */
+	scope: string;
+};
+
+export type Settings = {
+	typing: Partial<Record<LangCode, boolean>>;
+	audio: boolean;
+	romanization: boolean;
+	/** Daily XP goal. */
+	goal: number;
+};
+
+type Store = { version: 1; langs: Partial<Record<LangCode, LangProgress>>; settings: Settings };
+
+const KEY = 'language-learner-v1';
+
+const emptyLang = (): LangProgress => ({
+	lessons: {},
+	cards: {},
+	xp: 0,
+	days: {},
+	daily: {},
+	bests: {},
+	skills: {},
+	scope: ''
+});
+
+const empty = (): Store => ({
+	version: 1,
+	langs: {},
+	settings: { typing: {}, audio: true, romanization: true, goal: 50 }
+});
+
+function streakOf(days: Record<string, number>): number {
+	const today = dayNumber();
+	const active = new Set(
+		Object.entries(days)
+			.filter(([, xp]) => xp > 0)
+			.map(([key]) => dayNumber(key))
+	);
+	// An unfinished today does not break a streak that ran until yesterday.
+	let day = active.has(today) ? today : today - 1;
+	let streak = 0;
+	while (active.has(day)) {
+		streak++;
+		day--;
+	}
+	return streak;
+}
+
+class Progress {
+	data = $state<Store>(empty());
+	loaded = $state(false);
+
+	load() {
+		if (!browser || this.loaded) return;
+		try {
+			const raw = localStorage.getItem(KEY);
+			if (raw) this.data = { ...empty(), ...JSON.parse(raw) };
+		} catch {
+			// Unreadable progress starts fresh rather than breaking the page.
+		}
+		this.loaded = true;
+	}
+
+	save() {
+		if (!browser) return;
+		try {
+			localStorage.setItem(KEY, JSON.stringify(this.data));
+		} catch {
+			// Storage can be full or disabled; progress then lasts for this visit only.
+		}
+	}
+
+	lang(code: LangCode): LangProgress {
+		return (this.data.langs[code] ??= emptyLang());
+	}
+
+	get settings() {
+		return this.data.settings;
+	}
+
+	typing(code: LangCode) {
+		// Typing Hangul needs a Korean keyboard, so it starts off for Korean.
+		return this.data.settings.typing[code] ?? code !== 'ko';
+	}
+
+	answer(code: LangCode, entries: Entry[], correct: boolean) {
+		const p = this.lang(code);
+		const today = dayNumber();
+		for (const entry of entries)
+			p.cards[entry.id] = review(p.cards[entry.id] ?? newCard(today), correct, today);
+	}
+
+	skill(code: LangCode, skill: string, correct: boolean) {
+		const s = (this.lang(code).skills[skill] ??= { seen: 0, right: 0 });
+		s.seen++;
+		if (correct) s.right++;
+	}
+
+	addXp(code: LangCode, xp: number) {
+		const p = this.lang(code);
+		const key = dayKey();
+		p.xp += xp;
+		p.days[key] = (p.days[key] ?? 0) + xp;
+		this.save();
+	}
+
+	completeLesson(code: LangCode, lessonId: string, score: number, entries: Entry[]) {
+		const p = this.lang(code);
+		const record = p.lessons[lessonId];
+		p.lessons[lessonId] = {
+			best: Math.max(record?.best ?? 0, score),
+			runs: (record?.runs ?? 0) + 1,
+			last: dayKey()
+		};
+		const today = dayNumber();
+		for (const entry of entries) p.cards[entry.id] ??= newCard(today + 1);
+		this.save();
+	}
+
+	recordBest(code: LangCode, mode: string, score: number): boolean {
+		const p = this.lang(code);
+		const record = score > (p.bests[mode] ?? 0);
+		if (record) p.bests[mode] = score;
+		this.save();
+		return record;
+	}
+
+	recordDaily(code: LangCode, score: number) {
+		const p = this.lang(code);
+		p.daily[dayKey()] ??= score;
+		this.save();
+	}
+
+	todayXp(code?: LangCode): number {
+		const key = dayKey();
+		const codes = code ? [code] : (Object.keys(this.data.langs) as LangCode[]);
+		return codes.reduce((sum, c) => sum + (this.data.langs[c]?.days[key] ?? 0), 0);
+	}
+
+	streak(code?: LangCode): number {
+		if (code) return streakOf(this.data.langs[code]?.days ?? {});
+		const merged: Record<string, number> = {};
+		for (const p of Object.values(this.data.langs))
+			for (const [key, xp] of Object.entries(p.days)) merged[key] = (merged[key] ?? 0) + xp;
+		return streakOf(merged);
+	}
+
+	due(code: LangCode): string[] {
+		const today = dayNumber();
+		return Object.entries(this.data.langs[code]?.cards ?? {})
+			.filter(([, card]) => card.due <= today)
+			.sort(([, a], [, b]) => a.due - b.due)
+			.map(([id]) => id);
+	}
+
+	export(): string {
+		return JSON.stringify(this.data);
+	}
+
+	import(json: string) {
+		const parsed = JSON.parse(json) as Store;
+		if (parsed?.version !== 1 || typeof parsed.langs !== 'object')
+			throw new Error('Not a language learner backup');
+		this.data = { ...empty(), ...parsed };
+		this.save();
+	}
+
+	reset(code: LangCode) {
+		delete this.data.langs[code];
+		this.save();
+	}
+}
+
+export const progress = new Progress();

src/lib/language-learner/random.test.ts

@@ -0,0 +1,12 @@
+import { describe, expect, it } from 'vitest';
+import { sample, seeded } from './random';
+
+describe('sample', () => {
+	it('returns at most the requested number of distinct values', () => {
+		const rng = seeded(1);
+		expect(sample(rng, [1, 2, 3, 4, 5], 0)).toEqual([]);
+		expect(sample(rng, [1, 2, 3, 4, 5], 3)).toHaveLength(3);
+		expect(sample(rng, ['a', 'A', 'b'], 5)).toHaveLength(2);
+		expect(sample(rng, ['a', 'b', 'c'], 3, String, ['b'])).not.toContain('b');
+	});
+});

src/lib/language-learner/random.ts

@@ -0,0 +1,50 @@
+export type Rng = () => number;
+
+/** Small deterministic generator, so a daily challenge is the same all day. */
+export function seeded(seed: number | string): Rng {
+	let h = typeof seed === 'number' ? seed >>> 0 : 2166136261;
+	if (typeof seed === 'string') {
+		for (let i = 0; i < seed.length; i++) h = Math.imul(h ^ seed.charCodeAt(i), 16777619);
+	}
+	return () => {
+		h = (h + 0x6d2b79f5) >>> 0;
+		let t = h;
+		t = Math.imul(t ^ (t >>> 15), t | 1);
+		t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
+		return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
+	};
+}
+
+export const int = (rng: Rng, min: number, max: number) =>
+	min + Math.floor(rng() * (max - min + 1));
+
+export const pick = <T>(rng: Rng, list: readonly T[]): T => list[Math.floor(rng() * list.length)];
+
+export function shuffle<T>(rng: Rng, list: readonly T[]): T[] {
+	const copy = [...list];
+	for (let i = copy.length - 1; i > 0; i--) {
+		const j = Math.floor(rng() * (i + 1));
+		[copy[i], copy[j]] = [copy[j], copy[i]];
+	}
+	return copy;
+}
+
+/** Up to `count` distinct values from `list` that differ from `exclude` once normalized. */
+export function sample<T>(
+	rng: Rng,
+	list: readonly T[],
+	count: number,
+	key: (value: T) => string = String,
+	exclude: string[] = []
+): T[] {
+	const seen = new Set(exclude.map((value) => value.toLowerCase()));
+	const out: T[] = [];
+	for (const value of shuffle(rng, list)) {
+		if (out.length >= count) break;
+		const k = key(value).toLowerCase();
+		if (seen.has(k)) continue;
+		seen.add(k);
+		out.push(value);
+	}
+	return out;
+}

src/lib/language-learner/speech.ts

@@ -0,0 +1,43 @@
+/** Text-to-speech through the browser's built-in voices; no audio files or services. */
+
+const supported = () => typeof window !== 'undefined' && 'speechSynthesis' in window;
+
+function voices(): Promise<SpeechSynthesisVoice[]> {
+	if (!supported()) return Promise.resolve([]);
+	const now = speechSynthesis.getVoices();
+	if (now.length) return Promise.resolve(now);
+	return new Promise((resolve) => {
+		const done = () => resolve(speechSynthesis.getVoices());
+		speechSynthesis.addEventListener('voiceschanged', done, { once: true });
+		setTimeout(done, 1500);
+	});
+}
+
+const matches = (voice: SpeechSynthesisVoice, lang: string) =>
+	voice.lang.replace('_', '-').toLowerCase().startsWith(lang.slice(0, 2).toLowerCase());
+
+function best(list: SpeechSynthesisVoice[], lang: string) {
+	const candidates = list.filter((v) => matches(v, lang));
+	return (
+		candidates.find(
+			(v) => v.lang.replace('_', '-').toLowerCase() === lang.toLowerCase() && !v.localService
+		) ??
+		candidates.find((v) => v.lang.replace('_', '-').toLowerCase() === lang.toLowerCase()) ??
+		candidates[0]
+	);
+}
+
+export async function hasVoice(lang: string): Promise<boolean> {
+	return !!best(await voices(), lang);
+}
+
+export async function speak(text: string, lang: string, rate = 0.9) {
+	if (!supported()) return;
+	const voice = best(await voices(), lang);
+	speechSynthesis.cancel();
+	const utterance = new SpeechSynthesisUtterance(text);
+	utterance.lang = lang;
+	utterance.rate = rate;
+	if (voice) utterance.voice = voice;
+	speechSynthesis.speak(utterance);
+}

src/lib/language-learner/srs.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from 'vitest';
+import { dayKey, dayNumber, mastery, newCard, review } from './srs';
+
+describe('spaced repetition', () => {
+	it('grows intervals when answers are right and resets them when wrong', () => {
+		let card = newCard(100);
+		card = review(card, true, 100);
+		expect(card.due).toBe(101);
+		card = review(card, true, 101);
+		expect(card.due).toBe(104);
+		card = review(card, true, 104);
+		expect(card.interval).toBeGreaterThan(3);
+		card = review(card, false, 110);
+		expect(card).toMatchObject({ interval: 0, due: 110, lapses: 1 });
+	});
+
+	it('does not reschedule twice on the same day', () => {
+		let card = review(newCard(5), true, 5);
+		card = review(card, true, 5);
+		expect(card).toMatchObject({ reps: 1, due: 6, seen: 2 });
+		expect(mastery(card)).toBe('learning');
+	});
+
+	it('counts calendar days', () => {
+		expect(dayNumber('2026-03-02') - dayNumber('2026-02-27')).toBe(3);
+		expect(dayKey(new Date(2026, 0, 5))).toBe('2026-01-05');
+	});
+});

src/lib/language-learner/srs.ts

@@ -0,0 +1,76 @@
+/** A simplified SM-2 schedule. Days are counted as local calendar days. */
+
+export type Card = {
+	due: number;
+	interval: number;
+	ease: number;
+	reps: number;
+	lapses: number;
+	seen: number;
+	right: number;
+	last: number;
+};
+
+export function dayKey(date = new Date()): string {
+	const y = date.getFullYear();
+	const m = String(date.getMonth() + 1).padStart(2, '0');
+	const d = String(date.getDate()).padStart(2, '0');
+	return `${y}-${m}-${d}`;
+}
+
+export function dayNumber(key = dayKey()): number {
+	const [y, m, d] = key.split('-').map(Number);
+	return Math.round(Date.UTC(y, m - 1, d) / 86_400_000);
+}
+
+export const newCard = (today: number): Card => ({
+	due: today,
+	interval: 0,
+	ease: 2.5,
+	reps: 0,
+	lapses: 0,
+	seen: 0,
+	right: 0,
+	last: -1
+});
+
+export function review(card: Card, correct: boolean, today: number): Card {
+	const next = { ...card, seen: card.seen + 1, right: card.right + (correct ? 1 : 0) };
+	if (!correct) {
+		return {
+			...next,
+			reps: 0,
+			interval: 0,
+			lapses: card.lapses + 1,
+			ease: Math.max(1.3, card.ease - 0.2),
+			due: today,
+			last: today
+		};
+	}
+	// Grinding the same card again on one day should not push it months ahead.
+	if (card.last === today && card.reps > 0) return next;
+	const reps = card.reps + 1;
+	const interval =
+		reps === 1 ? 1 : reps === 2 ? 3 : Math.round(Math.max(card.interval, 1) * card.ease);
+	return {
+		...next,
+		reps,
+		interval,
+		ease: Math.min(3, card.ease + 0.05),
+		due: today + interval,
+		last: today
+	};
+}
+
+export type Mastery = 'new' | 'learning' | 'familiar' | 'known' | 'mastered';
+
+export function mastery(card: Card | undefined): Mastery {
+	if (!card || card.seen === 0) return 'new';
+	if (card.interval < 3) return 'learning';
+	if (card.interval < 14) return 'familiar';
+	if (card.interval < 60) return 'known';
+	return 'mastered';
+}
+
+/** 0 for new cards, approaching 1 for cards reviewed months apart. */
+export const strength = (card: Card | undefined) => (card ? Math.min(1, card.interval / 30) : 0);

src/lib/language-learner/text.ts

@@ -0,0 +1,67 @@
+/** Lowercase, strip punctuation and diacritics-insensitive comparison helpers for answers. */
+
+const PUNCTUATION = /[.,!?¿¡;:"“”„‘’'`()[\]{}…~·-]/g;
+
+export function normalize(value: string): string {
+	return value
+		.normalize('NFC')
+		.toLowerCase()
+		.replace(/[’‘`]/g, "'")
+		.replace(PUNCTUATION, ' ')
+		.replace(/\s+/g, ' ')
+		.trim();
+}
+
+export function stripDiacritics(value: string): string {
+	// Only Latin marks: decomposing Hangul would break Korean answers.
+	return value.replace(/[À-ɏ]/g, (c) => c.normalize('NFD').replace(/[̀-ͯ]/g, ''));
+}
+
+export function distance(a: string, b: string): number {
+	const row = Array.from({ length: b.length + 1 }, (_, i) => i);
+	for (let i = 1; i <= a.length; i++) {
+		let previous = row[0];
+		row[0] = i;
+		for (let j = 1; j <= b.length; j++) {
+			const current = row[j];
+			row[j] = Math.min(row[j] + 1, row[j - 1] + 1, previous + (a[i - 1] === b[j - 1] ? 0 : 1));
+			previous = current;
+		}
+	}
+	return row[b.length];
+}
+
+export type Verdict = 'correct' | 'accent' | 'typo' | 'wrong';
+
+/** Compare a typed answer with every accepted answer, forgiving accents and one-letter typos. */
+export function grade(input: string, accepted: string[]): { verdict: Verdict; match: string } {
+	const given = normalize(input);
+	let best: { verdict: Verdict; match: string } = { verdict: 'wrong', match: accepted[0] };
+	if (!given) return best;
+	for (const answer of accepted) {
+		const expected = normalize(answer);
+		if (given === expected) return { verdict: 'correct', match: answer };
+		if (stripDiacritics(given) === stripDiacritics(expected))
+			best = { verdict: 'accent', match: answer };
+		else if (
+			best.verdict === 'wrong' &&
+			[...expected].length >= 5 &&
+			distance(stripDiacritics(given), stripDiacritics(expected)) === 1
+		)
+			best = { verdict: 'typo', match: answer };
+	}
+	return best;
+}
+
+/** Split a sentence into word tiles, keeping punctuation attached to the word. */
+export function tiles(sentence: string): string[] {
+	return sentence.split(/\s+/).filter(Boolean);
+}
+
+export function sameTiles(a: string[], b: string[]): boolean {
+	return normalize(a.join(' ')) === normalize(b.join(' '));
+}
+
+/** Key for telling multiple-choice options apart; unlike `normalize` it keeps apostrophes (its / it's). */
+export const optionKey = (value: string) =>
+	value.normalize('NFC').trim().toLowerCase().replace(/\s+/g, ' ');

src/lib/language-learner/types.ts

@@ -0,0 +1,114 @@
+export type LangCode = 'nl' | 'ko' | 'en';
+
+export type EntryKind = 'word' | 'sentence' | 'script';
+
+/** Something to learn: a word, a sentence or a Hangul letter. */
+export type Entry = {
+	/** Stable across content edits, so spaced-repetition history survives reordering. */
+	id: string;
+	kind: EntryKind;
+	/** Accepted forms in the language being learned; the first is shown. */
+	target: string[];
+	/** Accepted translations (or romanization, for script entries); the first is shown. */
+	gloss: string[];
+	note?: string;
+	lesson: string;
+};
+
+/** A hand-written multiple-choice question about grammar. */
+export type Drill = { prompt: string; answer: string; wrong: string[]; explain?: string };
+
+export type Lesson = {
+	id: string;
+	title: string;
+	summary: string;
+	/** Markdown. */
+	notes: string;
+	words: Entry[];
+	sentences: Entry[];
+	drills: Drill[];
+	level: string;
+};
+
+export type Level = {
+	id: string;
+	title: string;
+	/** CEFR band, or "Hangul" for the Korean alphabet. */
+	band: string;
+	description: string;
+	lessons: Lesson[];
+};
+
+export type Course = {
+	code: LangCode;
+	name: string;
+	nativeName: string;
+	/** Language of translations and explanations. */
+	glossLang: LangCode;
+	/** BCP 47 tag for speech synthesis. */
+	voice: string;
+	tagline: string;
+	levels: Level[];
+};
+
+type Base = {
+	key: string;
+	instruction: string;
+	/** Entries this exercise tests; answers update their review schedule. */
+	entries: Entry[];
+	explain?: string;
+	/** Text to read aloud in the target language. */
+	audio?: string;
+	/** Hide the written prompt so the learner has to listen. */
+	listen?: boolean;
+	/** Skill name for endless drills, used in stats. */
+	skill?: string;
+};
+
+export type ChooseExercise = Base & {
+	type: 'choose';
+	prompt: string;
+	promptLang: 'target' | 'gloss';
+	/** Sentence context shown under the prompt, e.g. the translation of a cloze. */
+	context?: string;
+	options: string[];
+	answer: string;
+	optionLang: 'target' | 'gloss';
+};
+
+export type TypeExercise = Base & {
+	type: 'type';
+	prompt: string;
+	promptLang: 'target' | 'gloss';
+	context?: string;
+	accept: string[];
+	answerLang: 'target' | 'gloss';
+};
+
+export type BuildExercise = Base & {
+	type: 'build';
+	prompt: string;
+	answer: string;
+	tiles: string[];
+};
+
+export type MatchExercise = Base & {
+	type: 'match';
+	pairs: { target: string; gloss: string }[];
+};
+
+export type Exercise = ChooseExercise | TypeExercise | BuildExercise | MatchExercise;
+
+export type Answer = { correct: boolean; given: string; note?: string };
+
+export type SessionResult = {
+	answered: number;
+	correct: number;
+	/** Exercises answered right on the first try. */
+	firstTry: number;
+	total: number;
+	xp: number;
+	seconds: number;
+	mistakes: Exercise[];
+	reason: 'done' | 'lives' | 'time' | 'ended';
+};

src/lib/language-learner/ui/Exercise.svelte

@@ -0,0 +1,294 @@
+<script lang="ts">
+	import { onMount } from 'svelte';
+	import Volume2 from 'lucide-svelte/icons/volume-2';
+	import { romanize } from '../hangul';
+	import { speak } from '../speech';
+	import { grade, normalize } from '../text';
+	import type { Answer, Exercise, LangCode } from '../types';
+	import Speak from './Speak.svelte';
+
+	let {
+		exercise,
+		code,
+		glossLang,
+		voice,
+		audio,
+		romanization,
+		locked,
+		onanswer
+	}: {
+		exercise: Exercise;
+		code: LangCode;
+		glossLang: LangCode;
+		voice: string;
+		audio: boolean;
+		romanization: boolean;
+		locked: boolean;
+		onanswer: (answer: Answer) => void;
+	} = $props();
+
+	// Romanization would give away Hangul reading questions and grammar drills.
+	const showRoman = $derived(
+		code === 'ko' &&
+			romanization &&
+			!exercise.skill &&
+			!exercise.key.startsWith('drill:') &&
+			!exercise.entries.some((e) => e.kind === 'script')
+	);
+	const roman = (text: string) => (showRoman && /[가-힣]/.test(text) ? romanize(text) : '');
+	const langOf = (side: 'target' | 'gloss') => (side === 'target' ? code : glossLang);
+
+	let chosen = $state<string | null>(null);
+	let typed = $state('');
+	let picked = $state<number[]>([]);
+	let input = $state<HTMLInputElement>();
+
+	// match state
+	let left = $state<number | null>(null);
+	let right = $state<number | null>(null);
+	let matched = $state<number[]>([]);
+	let matchedRight = $state<number[]>([]);
+	let wrongFlash = $state(false);
+	let mistakes = $state(0);
+	const rightOrder = $derived.by(() => {
+		if (exercise.type !== 'match') return [];
+		// deterministic shuffle so the columns don't line up
+		return exercise.pairs.map((_, i) => i).sort((a, b) => ((a * 7 + 3) % 11) - ((b * 7 + 3) % 11));
+	});
+
+	onMount(() => {
+		if (exercise.listen && exercise.audio && audio) speak(exercise.audio, voice);
+		input?.focus();
+	});
+
+	function choose(option: string) {
+		if (locked || exercise.type !== 'choose') return;
+		chosen = option;
+		onanswer({ correct: option === exercise.answer, given: option });
+	}
+
+	function submitTyped() {
+		if (locked || exercise.type !== 'type' || !typed.trim()) return;
+		const { verdict, match } = grade(typed, exercise.accept);
+		onanswer({
+			correct: verdict !== 'wrong',
+			given: typed,
+			note:
+				verdict === 'accent'
+					? `Mind the accents: ${match}`
+					: verdict === 'typo'
+						? `Almost! Watch the spelling: ${match}`
+						: undefined
+		});
+	}
+
+	function submitBuilt() {
+		if (locked || exercise.type !== 'build' || !picked.length) return;
+		const given = picked.map((i) => exercise.tiles[i]).join(' ');
+		const accepted = [exercise.answer, ...exercise.entries.flatMap((e) => e.target)];
+		onanswer({ correct: accepted.some((a) => normalize(a) === normalize(given)), given });
+	}
+
+	function pickPair(side: 'left' | 'right', index: number) {
+		if (locked || exercise.type !== 'match') return;
+		if (side === 'left') left = index;
+		else right = index;
+		if (left === null || right === null) return;
+		// Compare texts rather than positions, in case two pairs look alike.
+		if (exercise.pairs[left].gloss === exercise.pairs[right].gloss) {
+			matched = [...matched, left];
+			matchedRight = [...matchedRight, right];
+			if (matched.length === exercise.pairs.length) onanswer({ correct: mistakes <= 1, given: '' });
+		} else {
+			mistakes++;
+			wrongFlash = true;
+			setTimeout(() => (wrongFlash = false), 350);
+		}
+		left = null;
+		right = null;
+	}
+
+	function onkeydown(event: KeyboardEvent) {
+		if (locked || event.defaultPrevented || event.target instanceof HTMLInputElement) return;
+		if (exercise.type === 'choose' && /^[1-9]$/.test(event.key)) {
+			const option = exercise.options[Number(event.key) - 1];
+			if (option) {
+				event.preventDefault();
+				choose(option);
+			}
+		}
+		if (exercise.type === 'build') {
+			if (event.key === 'Enter') {
+				event.preventDefault();
+				submitBuilt();
+			} else if (event.key === 'Backspace') {
+				event.preventDefault();
+				picked = picked.slice(0, -1);
+			}
+		}
+	}
+
+	const optionState = (option: string) => {
+		if (exercise.type !== 'choose' || !locked) return '';
+		if (option === exercise.answer) return 'is-right';
+		if (option === chosen) return 'is-wrong';
+		return 'is-dim';
+	};
+</script>
+
+<svelte:window {onkeydown} />
+
+<div class="ll-exercise">
+	<p class="ll-instruction">{exercise.instruction}</p>
+
+	{#if exercise.type === 'choose' || exercise.type === 'type'}
+		<div class="ll-prompt">
+			{#if exercise.listen && exercise.audio && audio}
+				<button
+					type="button"
+					class="ll-listen"
+					aria-label="Play again"
+					onclick={() => speak(exercise.audio!, voice)}
+					><Volume2 size={36} aria-hidden="true" /></button
+				>
+				<button type="button" class="ll-slow" onclick={() => speak(exercise.audio!, voice, 0.6)}
+					>slower</button
+				>
+			{:else}
+				<p class="ll-prompt-text" lang={langOf(exercise.promptLang)}>
+					{exercise.prompt}
+					{#if exercise.audio && audio && exercise.promptLang === 'target'}
+						<Speak text={exercise.audio} {voice} />
+					{/if}
+				</p>
+				{#if exercise.promptLang === 'target' && roman(exercise.prompt)}
+					<p class="ll-roman">{roman(exercise.prompt)}</p>
+				{/if}
+			{/if}
+			{#if exercise.context}
+				<p class="ll-context">{exercise.context}</p>
+			{/if}
+		</div>
+	{/if}
+
+	{#if exercise.type === 'choose'}
+		<div class="ll-options" class:ll-options-wide={exercise.options.some((o) => o.length > 28)}>
+			{#each exercise.options as option, i (option)}
+				<button
+					type="button"
+					class="ll-option {optionState(option)}"
+					class:is-glyph={[...option].length <= 2 && /[\u3131-\u318e가-힣]/.test(option)}
+					disabled={locked}
+					onclick={() => choose(option)}
+				>
+					<kbd>{i + 1}</kbd>
+					<span lang={langOf(exercise.optionLang)}>
+						{option}
+						{#if exercise.optionLang === 'target' && roman(option)}
+							<small class="ll-roman">{roman(option)}</small>
+						{/if}
+					</span>
+				</button>
+			{/each}
+		</div>
+	{:else if exercise.type === 'type'}
+		<form
+			class="ll-type"
+			onsubmit={(event) => {
+				event.preventDefault();
+				submitTyped();
+			}}
+		>
+			<input
+				bind:this={input}
+				bind:value={typed}
+				lang={langOf(exercise.answerLang)}
+				disabled={locked}
+				autocomplete="off"
+				autocapitalize="off"
+				spellcheck="false"
+				aria-label="Your answer"
+				placeholder={exercise.answerLang === 'target'
+					? `Type in ${code === 'ko' ? 'Korean' : code === 'nl' ? 'Dutch' : 'English'}`
+					: 'Type your answer'}
+				onkeydown={(event) => {
+					if (event.key === 'Enter') {
+						event.preventDefault();
+						submitTyped();
+					}
+				}}
+			/>
+			<button type="submit" class="ll-button" disabled={locked || !typed.trim()}>Check</button>
+		</form>
+		{#if code === 'ko' && exercise.answerLang === 'target'}
+			<p class="ll-hint">
+				Needs a Korean keyboard. Turn typing off in the settings if you don't have one.
+			</p>
+		{/if}
+	{:else if exercise.type === 'build'}
+		<div class="ll-prompt">
+			<p class="ll-prompt-text" lang={glossLang}>{exercise.prompt}</p>
+		</div>
+		<div class="ll-build-line" lang={code} aria-label="Your sentence">
+			{#each picked as tileIndex, i (tileIndex)}
+				<button
+					type="button"
+					class="ll-tile"
+					disabled={locked}
+					onclick={() => (picked = picked.filter((_, j) => j !== i))}
+					>{exercise.tiles[tileIndex]}</button
+				>
+			{:else}
+				<span class="ll-hint">Tap the words in the right order</span>
+			{/each}
+		</div>
+		<div class="ll-bank" lang={code}>
+			{#each exercise.tiles as tile, i (i)}
+				<button
+					type="button"
+					class="ll-tile"
+					class:is-used={picked.includes(i)}
+					disabled={locked || picked.includes(i)}
+					onclick={() => (picked = [...picked, i])}>{tile}</button
+				>
+			{/each}
+		</div>
+		<div class="ll-actions">
+			<button
+				type="button"
+				class="ll-button"
+				disabled={locked || !picked.length}
+				onclick={submitBuilt}>Check</button
+			>
+		</div>
+	{:else if exercise.type === 'match'}
+		<div class="ll-match" class:is-shaking={wrongFlash}>
+			<div>
+				{#each exercise.pairs as pair, i (i)}
+					<button
+						type="button"
+						class="ll-option"
+						class:is-selected={left === i}
+						class:is-matched={matched.includes(i)}
+						disabled={locked || matched.includes(i)}
+						lang={code}
+						onclick={() => pickPair('left', i)}>{pair.target}</button
+					>
+				{/each}
+			</div>
+			<div>
+				{#each rightOrder as i (i)}
+					<button
+						type="button"
+						class="ll-option"
+						class:is-selected={right === i}
+						class:is-matched={matchedRight.includes(i)}
+						disabled={locked || matchedRight.includes(i)}
+						lang={glossLang}
+						onclick={() => pickPair('right', i)}>{exercise.pairs[i].gloss}</button
+					>
+				{/each}
+			</div>
+		</div>
+	{/if}
+</div>

src/lib/language-learner/ui/Results.svelte

@@ -0,0 +1,79 @@
+<script lang="ts">
+	import type { Snippet } from 'svelte';
+	import type { LangCode, SessionResult } from '../types';
+
+	let {
+		result,
+		code,
+		glossLang,
+		title,
+		subtitle,
+		score,
+		percent = false,
+		record = false,
+		children
+	}: {
+		result: SessionResult;
+		code: LangCode;
+		glossLang: LangCode;
+		title: string;
+		subtitle?: string;
+		/** Headline number; defaults to accuracy. */
+		score?: number;
+		/** Show the score as a percentage. */
+		percent?: boolean;
+		record?: boolean;
+		children?: Snippet;
+	} = $props();
+
+	const accuracy = $derived(
+		result.answered ? Math.round((result.correct / result.answered) * 100) : 0
+	);
+	const unique = $derived([...new Map(result.mistakes.map((m) => [m.key, m])).values()]);
+
+	function answerOf(m: SessionResult['mistakes'][number]) {
+		if (m.type === 'choose') return m.answer;
+		if (m.type === 'type') return m.accept[0];
+		if (m.type === 'build') return m.answer;
+		return '';
+	}
+</script>
+
+<section class="ll-card mb-10" aria-live="polite">
+	<p class="text-sm ll-muted">{subtitle}</p>
+	<h2 class="mb-4 text-3xl font-semibold">{title}{record ? ' · new best!' : ''}</h2>
+	<div class="mb-6 grid grid-cols-3 gap-3 text-center">
+		<div>
+			<p class="text-3xl font-semibold">
+				{score ?? accuracy}{score === undefined || percent ? '%' : ''}
+			</p>
+			<p class="text-sm ll-muted">{score === undefined ? 'accuracy' : 'score'}</p>
+		</div>
+		<div>
+			<p class="text-3xl font-semibold">{result.correct}/{result.answered}</p>
+			<p class="text-sm ll-muted">right</p>
+		</div>
+		<div>
+			<p class="text-3xl font-semibold">+{result.xp}</p>
+			<p class="text-sm ll-muted">XP</p>
+		</div>
+	</div>
+	{#if unique.length}
+		<h3 class="mb-2 font-semibold">to look at again</h3>
+		<ul
+			class="mb-6 divide-y divide-[var(--site-border)] border-y border-[var(--site-border)] text-sm"
+		>
+			{#each unique.slice(0, 12) as m (m.key)}
+				<li class="flex flex-wrap justify-between gap-x-4 py-2">
+					<span lang={m.type === 'build' ? glossLang : undefined}
+						>{m.type === 'match' ? 'Matching pairs' : m.prompt}</span
+					>
+					<strong lang={code}>{answerOf(m)}</strong>
+				</li>
+			{/each}
+		</ul>
+	{/if}
+	<div class="flex flex-wrap gap-2">
+		{@render children?.()}
+	</div>
+</section>

src/lib/language-learner/ui/Session.svelte

@@ -0,0 +1,246 @@
+<script lang="ts">
+	import { onDestroy, onMount, untrack } from 'svelte';
+	import Heart from 'lucide-svelte/icons/heart';
+	import Timer from 'lucide-svelte/icons/timer';
+	import X from 'lucide-svelte/icons/x';
+	import ProgressBar from '$lib/components/ProgressBar.svelte';
+	import { progress } from '../progress.svelte';
+	import { speak } from '../speech';
+	import type { Answer, Course, Exercise, SessionResult } from '../types';
+	import ExerciseView from './Exercise.svelte';
+
+	let {
+		course,
+		queue: initial,
+		more,
+		requeue = false,
+		lives,
+		seconds,
+		xpPer = 2,
+		audio,
+		onfinish
+	}: {
+		course: Course;
+		queue: Exercise[];
+		/** Supplies another exercise when the queue runs out; makes the session endless. */
+		more?: () => Exercise | null;
+		/** Ask wrongly answered exercises again at the end. */
+		requeue?: boolean;
+		lives?: number;
+		seconds?: number;
+		xpPer?: number;
+		audio: boolean;
+		onfinish: (result: SessionResult) => void;
+	} = $props();
+
+	const code = $derived(course.code);
+	// The parent remounts the session for every run, so the starting props are all it needs.
+	const config = untrack(() => ({ queue: [...initial], more, lives, seconds }));
+	const queue = config.queue;
+	const firstCount = queue.length;
+	const attempted = new WeakSet<Exercise>();
+	let unique = 0;
+	const started = Date.now();
+
+	let current = $state<Exercise | null>(queue.shift() ?? config.more?.() ?? null);
+	let turn = $state(0);
+	let locked = $state(false);
+	let feedback = $state<(Answer & { expected: string }) | null>(null);
+	let answered = $state(0);
+	let correct = $state(0);
+	let firstTry = $state(0);
+	let xp = $state(0);
+	let combo = $state(0);
+	let requeued = $state(0);
+	let livesLeft = $state(config.lives ?? 0);
+	let timeLeft = $state(config.seconds ?? 0);
+	let mistakes: Exercise[] = [];
+	let finished = false;
+	let advanceTimer: ReturnType<typeof setTimeout> | undefined;
+	let clock: ReturnType<typeof setInterval> | undefined;
+
+	onMount(() => {
+		if (!current) finish('done');
+		if (seconds)
+			clock = setInterval(() => {
+				timeLeft = Math.max(0, seconds - Math.floor((Date.now() - started) / 1000));
+				if (timeLeft === 0) finish('time');
+			}, 250);
+	});
+
+	onDestroy(() => {
+		clearInterval(clock);
+		clearTimeout(advanceTimer);
+	});
+
+	function expectedOf(ex: Exercise): string {
+		if (ex.type === 'choose') return ex.answer;
+		if (ex.type === 'type') return ex.accept[0];
+		if (ex.type === 'build') return ex.answer;
+		return '';
+	}
+
+	function answer(result: Answer) {
+		if (!current || locked) return;
+		const ex = current;
+		const first = !attempted.has(ex);
+		if (first) unique++;
+		attempted.add(ex);
+		answered++;
+		locked = true;
+		feedback = { ...result, expected: expectedOf(ex) };
+		progress.answer(code, ex.entries, result.correct);
+		if (ex.skill) progress.skill(code, ex.skill, result.correct);
+		if (result.correct) {
+			correct++;
+			if (first) firstTry++;
+			combo++;
+			// a small bonus for streaks of right answers keeps grinding rewarding
+			const gained = xpPer + (combo > 0 && combo % 10 === 0 ? 5 : 0);
+			xp += gained;
+			progress.addXp(code, gained);
+		} else {
+			combo = 0;
+			mistakes.push(ex);
+			if (requeue) {
+				queue.push(ex);
+				requeued++;
+			}
+			if (lives) livesLeft--;
+			progress.save();
+		}
+		if (audio && ex.audio && !ex.listen) speak(ex.audio, course.voice);
+		if (result.correct && !result.note) advanceTimer = setTimeout(next, seconds ? 350 : 900);
+	}
+
+	function next() {
+		clearTimeout(advanceTimer);
+		if (finished) return;
+		if (lives && livesLeft <= 0) return finish('lives');
+		const upcoming = queue.shift() ?? more?.() ?? null;
+		if (!upcoming) return finish('done');
+		current = upcoming;
+		turn++;
+		locked = false;
+		feedback = null;
+	}
+
+	function finish(reason: SessionResult['reason']) {
+		if (finished) return;
+		finished = true;
+		clearInterval(clock);
+		clearTimeout(advanceTimer);
+		onfinish({
+			answered,
+			correct,
+			firstTry,
+			total: unique,
+			xp,
+			seconds: Math.round((Date.now() - started) / 1000),
+			mistakes,
+			reason
+		});
+	}
+
+	function onkeydown(event: KeyboardEvent) {
+		if (!locked || event.defaultPrevented) return;
+		if (event.key === 'Enter' || event.key === ' ') {
+			event.preventDefault();
+			next();
+		}
+	}
+
+	const endless = $derived(!!more);
+	const expectedLang = $derived(
+		current?.type === 'choose'
+			? current.optionLang
+			: current?.type === 'type'
+				? current.answerLang
+				: 'target'
+	);
+</script>
+
+<svelte:window {onkeydown} />
+
+<div class="ll-session">
+	<div class="ll-session-top">
+		<button
+			type="button"
+			class="ll-icon-button"
+			aria-label="End session"
+			title="End session"
+			onclick={() => finish('ended')}><X size={20} aria-hidden="true" /></button
+		>
+		<div class="min-w-0 flex-1">
+			{#if seconds}
+				<ProgressBar value={timeLeft} max={seconds} label="Time left" />
+			{:else if !endless}
+				<ProgressBar value={correct} max={firstCount + requeued} label="Session progress" />
+			{:else}
+				<p class="ll-stat-line">{correct} right · {answered - correct} wrong</p>
+			{/if}
+		</div>
+		{#if seconds}
+			<span class="ll-pill"><Timer size={16} aria-hidden="true" /> {timeLeft}s</span>
+		{/if}
+		{#if lives}
+			<span class="ll-pill" aria-label="{livesLeft} lives left">
+				{#each Array.from({ length: lives }, (_, i) => i) as i (i)}
+					<Heart
+						size={16}
+						aria-hidden="true"
+						class={i < livesLeft ? 'll-heart' : 'll-heart-lost'}
+					/>
+				{/each}
+			</span>
+		{/if}
+		{#if combo >= 3}
+			<span class="ll-pill ll-combo">{combo} in a row</span>
+		{/if}
+		<span class="ll-pill">{xp} XP</span>
+	</div>
+
+	{#if current}
+		{#key turn}
+			<ExerciseView
+				exercise={current}
+				{code}
+				glossLang={course.glossLang}
+				voice={course.voice}
+				{audio}
+				romanization={progress.settings.romanization}
+				{locked}
+				onanswer={answer}
+			/>
+		{/key}
+	{/if}
+
+	{#if feedback}
+		<div
+			class="ll-feedback"
+			class:is-right={feedback.correct}
+			class:is-wrong={!feedback.correct}
+			role="status"
+		>
+			<div class="min-w-0">
+				<p class="font-semibold">
+					{feedback.correct ? (feedback.note ? 'Correct, almost' : 'Correct!') : 'Not quite'}
+				</p>
+				{#if feedback.note}
+					<p lang={code}>{feedback.note}</p>
+				{:else if !feedback.correct && feedback.expected}
+					<p>
+						Answer: <strong lang={expectedLang === 'target' ? code : course.glossLang}
+							>{feedback.expected}</strong
+						>
+					</p>
+				{/if}
+				{#if current?.explain && (!feedback.correct || feedback.note)}
+					<p class="ll-explain">{current.explain}</p>
+				{/if}
+			</div>
+			<button type="button" class="ll-button" onclick={next}>Continue</button>
+		</div>
+	{/if}
+	<p class="ll-keys">Keys: 1–4 to choose, Enter to check and continue.</p>
+</div>

src/lib/language-learner/ui/Speak.svelte

@@ -0,0 +1,22 @@
+<script lang="ts">
+	import Volume2 from 'lucide-svelte/icons/volume-2';
+	import { speak } from '../speech';
+
+	let {
+		text,
+		voice,
+		size = 18,
+		label = 'Listen'
+	}: { text: string; voice: string; size?: number; label?: string } = $props();
+</script>
+
+<button
+	type="button"
+	class="ll-speak"
+	aria-label={label}
+	title={label}
+	onclick={(event) => {
+		event.stopPropagation();
+		speak(text, voice);
+	}}><Volume2 {size} aria-hidden="true" /></button
+>

src/lib/projects.ts

@@ -35,6 +35,12 @@ export const projects = [
 		href: '/projects/world-opinions',
 		external: false
 	},
+	{
+		name: 'language learner',
+		subtitle: 'Dutch, Korean and English, from zero to fluent',
+		href: '/projects/language-learner',
+		external: false
+	},
 	{
 		name: 'money tracker',
 		subtitle: 'a manual ledger for accounts, bills and utilities',

src/lib/seo.ts

@@ -9,7 +9,9 @@ type Article = {
 };
 type List = { name: string; isProgress: boolean; items: { name: string }[] };
 type Race = { short: string; distance: number; discipline: string };
-type PageContent = { blogArticle?: Article; list?: List; race?: Race };
+/** Pages that describe themselves, such as language learner lessons. */
+type Described = { title: string; description: string; index?: boolean };
+type PageContent = { blogArticle?: Article; list?: List; race?: Race; seo?: Described };
 
 type Seo = {
 	title: string;
@@ -49,6 +51,11 @@ const publicPages: Record<string, { title: string; description: string }> = {
 		title: 'osu! map finder',
 		description: 'Find osu! beatmaps for Spotify songs, albums and playlists.'
 	},
+	'/projects/language-learner': {
+		title: 'Language Learner',
+		description:
+			'Learn Dutch, Korean and English from beginner to advanced, with lessons and endless daily challenges.'
+	},
 	'/projects/world-opinions': {
 		title: 'World Opinions',
 		description:
@@ -102,6 +109,8 @@ export function getSeo(
 				? `${list.name}: ${names.join(', ')}${list.items.length > names.length ? ', and more' : ''}.`
 				: `${list.name}, a ${list.isProgress ? 'progress ' : ''}list by Stan Runge.`
 		};
+	} else if (content.seo) {
+		page = content.seo;
 	} else if (/^\/projects\/derby\/[^/]+$/.test(path) && content.race) {
 		const race = content.race;
 		page = {
@@ -114,7 +123,8 @@ export function getSeo(
 		title: page ? formatTitle(page.title, environment) : getTitle(path, environment),
 		description: page?.description ?? 'Stan Runge’s personal website.',
 		url,
-		indexable: !!page && !environment && !/^\/blog\/[^/]+\/edit$/.test(path),
+		indexable:
+			!!page && !environment && !/^\/blog\/[^/]+\/edit$/.test(path) && content.seo?.index !== false,
 		type,
 		image: `${SITE_ORIGIN}/moon.jpg`,
 		imageAlt: 'Moon icon for Stan Runge’s website',

src/lib/title.ts

@@ -29,6 +29,7 @@ export function getTitle(path: string, environment: SiteEnvironment = null): str
 		'/projects/derby': 'Derby Lens',
 		'/projects/cs-prices': 'CS Prices',
 		'/projects/game-tracker': 'Game Tracker',
+		'/projects/language-learner': 'Language Learner',
 		'/projects/money-tracker': 'Money Tracker',
 		'/projects/spotify-beatmap-finder': 'osu! map finder',
 		'/projects/progress': 'Progress',

src/routes/projects/+page.svelte

@@ -10,6 +10,7 @@
 		{ name: 'cs prices', href: '/projects/cs-prices', external: false },
 		{ name: 'osu! map finder', href: '/projects/spotify-beatmap-finder', external: false },
 		{ name: 'game tracker', href: '/projects/game-tracker', external: false },
+		{ name: 'language learner', href: '/projects/language-learner', external: false },
 		{ name: 'money tracker', href: '/projects/money-tracker', external: false },
 		{ name: 'world opinions', href: '/projects/world-opinions', external: false },
 		{ name: 'vash esports', href: 'https://esports.vash.software', external: true },

src/routes/projects/language-learner/+layout.svelte

@@ -0,0 +1,13 @@
+<script lang="ts">
+	import './language-learner.css';
+	import { onMount } from 'svelte';
+	import { progress } from '$lib/language-learner/progress.svelte';
+
+	let { children } = $props();
+
+	onMount(() => progress.load());
+</script>
+
+<div class="ll mx-auto max-w-6xl px-4 py-10 sm:px-6 sm:py-14">
+	{@render children()}
+</div>

src/routes/projects/language-learner/+page.server.ts

@@ -0,0 +1,20 @@
+import { allEntries, allLessons } from '$lib/language-learner/course';
+import { COURSES, loadCourse } from '$lib/language-learner/courses';
+import type { PageServerLoad } from './$types';
+
+// Counted on the server so the overview doesn't download three full courses.
+export const load: PageServerLoad = async () => {
+	const courses = await Promise.all(COURSES.map((c) => loadCourse(c.code)));
+	return {
+		counts: Object.fromEntries(
+			courses.map((c) => [
+				c.code,
+				{
+					lessons: allLessons(c).length,
+					words: allEntries(c).filter((e) => e.kind === 'word').length,
+					levels: c.levels.map((lv) => lv.band)
+				}
+			])
+		) as Record<string, { lessons: number; words: number; levels: string[] }>
+	};
+};

src/routes/projects/language-learner/+page.svelte

@@ -0,0 +1,245 @@
+<script lang="ts">
+	import { resolve } from '$app/paths';
+	import ArrowRight from 'lucide-svelte/icons/arrow-right';
+	import Flame from 'lucide-svelte/icons/flame';
+	import ProgressBar from '$lib/components/ProgressBar.svelte';
+	import { COURSES } from '$lib/language-learner/courses';
+	import { progress } from '$lib/language-learner/progress.svelte';
+	import type { LangCode } from '$lib/language-learner/types';
+
+	let { data } = $props();
+
+	const goals = [20, 50, 100, 200];
+	let importError = $state('');
+	let fileInput = $state<HTMLInputElement>();
+
+	const completed = (code: LangCode) =>
+		Object.keys(progress.data.langs[code]?.lessons ?? {}).length;
+
+	function exportProgress() {
+		const blob = new Blob([progress.export()], { type: 'application/json' });
+		const link = document.createElement('a');
+		link.href = URL.createObjectURL(blob);
+		link.download = `language-learner-${new Date().toISOString().slice(0, 10)}.json`;
+		link.click();
+		URL.revokeObjectURL(link.href);
+	}
+
+	async function importProgress(event: Event) {
+		const file = (event.currentTarget as HTMLInputElement).files?.[0];
+		if (!file) return;
+		try {
+			progress.import(await file.text());
+			importError = '';
+		} catch {
+			importError = 'That file is not a language learner backup.';
+		}
+	}
+
+	function reset(code: LangCode, name: string) {
+		if (confirm(`Delete all ${name} progress? This can't be undone.`)) progress.reset(code);
+	}
+</script>
+
+<header class="mb-10">
+	<h1 class="mb-3 text-4xl font-semibold tracking-tight sm:text-5xl">language learner</h1>
+	<p class="max-w-2xl text-lg ll-muted">
+		Dutch, Korean and English from the very first word to advanced. Structured lessons from A1 to
+		C1, spaced repetition, and endless daily challenges to grind.
+	</p>
+</header>
+
+{#if progress.loaded}
+	<section class="mb-10 grid gap-3 sm:grid-cols-3" aria-label="Today">
+		<div class="ll-card">
+			<p class="text-sm ll-muted">streak</p>
+			<p class="flex items-center gap-2 text-3xl font-semibold">
+				<Flame
+					size={26}
+					aria-hidden="true"
+					class={progress.streak() ? 'text-[var(--ll-gold)]' : 'll-muted'}
+				/>
+				{progress.streak()}
+				{progress.streak() === 1 ? 'day' : 'days'}
+			</p>
+		</div>
+		<div class="ll-card">
+			<p class="text-sm ll-muted">today</p>
+			<p class="mb-2 text-3xl font-semibold">
+				{progress.todayXp()}
+				<span class="text-base font-normal ll-muted">/ {progress.settings.goal} XP</span>
+			</p>
+			<ProgressBar
+				value={Math.min(progress.todayXp(), progress.settings.goal)}
+				max={progress.settings.goal}
+				label="Daily goal"
+				small
+			/>
+		</div>
+		<div class="ll-card">
+			<p class="text-sm ll-muted">total</p>
+			<p class="text-3xl font-semibold">
+				{Object.values(progress.data.langs).reduce((n, p) => n + (p?.xp ?? 0), 0)} XP
+			</p>
+		</div>
+	</section>
+{/if}
+
+<section aria-label="Languages" class="mb-14 grid gap-4 md:grid-cols-3">
+	{#each COURSES as c (c.code)}
+		{@const count = data.counts[c.code]}
+		<a
+			href={resolve('/projects/language-learner/[lang]', { lang: c.code })}
+			class="ll-card flex flex-col gap-3"
+		>
+			<div class="flex items-center justify-between">
+				<span class="ll-badge">{c.code.toUpperCase()}</span>
+				{#if progress.loaded && progress.streak(c.code)}
+					<span class="ll-pill"
+						><Flame size={14} aria-hidden="true" /> {progress.streak(c.code)}</span
+					>
+				{/if}
+			</div>
+			<div>
+				<h2 class="text-2xl font-semibold">{c.name}</h2>
+				<p class="ll-muted" lang={c.code}>{c.nativeName}</p>
+			</div>
+			<p class="text-sm ll-muted" lang={c.glossLang}>{c.tagline}</p>
+			<p class="text-sm ll-muted">
+				{count.lessons} lessons · {count.words} words · {count.levels[0]}–{count.levels.at(-1)}
+			</p>
+			<div class="mt-auto">
+				{#if progress.loaded}
+					<div class="mb-1 flex justify-between text-sm">
+						<span>{completed(c.code)} / {count.lessons} lessons</span>
+						{#if progress.due(c.code).length}
+							<span class="ll-muted">{progress.due(c.code).length} to review</span>
+						{/if}
+					</div>
+					<ProgressBar
+						value={completed(c.code)}
+						max={count.lessons}
+						label="{c.name} lessons done"
+						small
+					/>
+				{/if}
+				<span class="mt-4 inline-flex items-center gap-1 font-semibold"
+					>{completed(c.code) ? 'Continue' : 'Start'}
+					<ArrowRight size={16} aria-hidden="true" /></span
+				>
+			</div>
+		</a>
+	{/each}
+</section>
+
+<section class="mb-14 grid gap-8 md:grid-cols-2">
+	<div>
+		<h2 class="mb-4 text-2xl font-semibold">how it works</h2>
+		<ul class="space-y-3 ll-muted">
+			<li>
+				<strong class="text-[var(--site-text)]">Lessons</strong> explain one topic, then drill its words,
+				sentences and grammar. Wrong answers come back until you get them right.
+			</li>
+			<li>
+				<strong class="text-[var(--site-text)]">Reviews</strong> use spaced repetition: every word you
+				learn returns just before you'd forget it.
+			</li>
+			<li>
+				<strong class="text-[var(--site-text)]">Challenges</strong> are endless: a daily challenge, a
+				60-second sprint, survival with three lives, and generated drills for numbers, clock times, conjugation,
+				articles and particles.
+			</li>
+			<li>
+				<strong class="text-[var(--site-text)]">Start anywhere.</strong> Lessons are never locked, and
+				a level test lets you skip what you already know.
+			</li>
+		</ul>
+	</div>
+	<div>
+		<h2 class="mb-4 text-2xl font-semibold">settings</h2>
+		{#if progress.loaded}
+			<div class="ll-card space-y-4">
+				<label class="flex items-center justify-between gap-4">
+					<span
+						>Read words aloud <span class="block text-sm ll-muted">Uses your browser's voices</span
+						></span
+					>
+					<input
+						type="checkbox"
+						bind:checked={progress.settings.audio}
+						onchange={() => progress.save()}
+					/>
+				</label>
+				<label class="flex items-center justify-between gap-4">
+					<span>Show romanization for Korean</span>
+					<input
+						type="checkbox"
+						bind:checked={progress.settings.romanization}
+						onchange={() => progress.save()}
+					/>
+				</label>
+				{#each COURSES as c (c.code)}
+					<label class="flex items-center justify-between gap-4">
+						<span>Typing exercises in {c.name}</span>
+						<input
+							type="checkbox"
+							checked={progress.typing(c.code)}
+							onchange={(event) => {
+								progress.settings.typing[c.code] = event.currentTarget.checked;
+								progress.save();
+							}}
+						/>
+					</label>
+				{/each}
+				<div class="flex flex-wrap items-center justify-between gap-3">
+					<span>Daily goal</span>
+					<div class="flex gap-2">
+						{#each goals as goal (goal)}
+							<button
+								type="button"
+								class="ll-chip"
+								aria-pressed={progress.settings.goal === goal}
+								onclick={() => {
+									progress.settings.goal = goal;
+									progress.save();
+								}}>{goal} XP</button
+							>
+						{/each}
+					</div>
+				</div>
+				<div class="border-t border-[var(--site-border)] pt-4">
+					<p class="mb-3 text-sm ll-muted">
+						Progress is saved in this browser. Export it to move it to another device.
+					</p>
+					<div class="flex flex-wrap gap-2">
+						<button type="button" class="ll-button ll-button-quiet" onclick={exportProgress}
+							>Export</button
+						>
+						<button
+							type="button"
+							class="ll-button ll-button-quiet"
+							onclick={() => fileInput?.click()}>Import</button
+						>
+						<input
+							bind:this={fileInput}
+							type="file"
+							accept="application/json"
+							class="hidden"
+							onchange={importProgress}
+						/>
+						{#each COURSES as c (c.code)}
+							{#if progress.data.langs[c.code]}
+								<button
+									type="button"
+									class="ll-button ll-button-quiet"
+									onclick={() => reset(c.code, c.name)}>Reset {c.name}</button
+								>
+							{/if}
+						{/each}
+					</div>
+					{#if importError}<p class="mt-2 text-sm text-[var(--ll-wrong)]">{importError}</p>{/if}
+				</div>
+			</div>
+		{/if}
+	</div>
+</section>

src/routes/projects/language-learner/[lang]/+layout.ts

@@ -0,0 +1,10 @@
+import { error } from '@sveltejs/kit';
+import { isLang, loadCourse } from '$lib/language-learner/courses';
+import { loadDrills } from '$lib/language-learner/drills';
+import type { LayoutLoad } from './$types';
+
+export const load: LayoutLoad = async ({ params }) => {
+	if (!isLang(params.lang)) error(404, 'Unknown language');
+	const [course, drills] = await Promise.all([loadCourse(params.lang), loadDrills(params.lang)]);
+	return { course, drills };
+};

src/routes/projects/language-learner/[lang]/+page.svelte

@@ -0,0 +1,211 @@
+<script lang="ts">
+	import { resolve } from '$app/paths';
+	import ArrowLeft from 'lucide-svelte/icons/arrow-left';
+	import Check from 'lucide-svelte/icons/check';
+	import Flame from 'lucide-svelte/icons/flame';
+	import ProgressBar from '$lib/components/ProgressBar.svelte';
+	import { allLessons } from '$lib/language-learner/course';
+	import { progress } from '$lib/language-learner/progress.svelte';
+	import { dayKey } from '$lib/language-learner/srs';
+	import { MODES } from '$lib/language-learner/modes';
+
+	let { data } = $props();
+	const course = $derived(data.course);
+	const code = $derived(course.code);
+	const p = $derived(progress.loaded ? progress.data.langs[code] : undefined);
+	const lessons = $derived(allLessons(course));
+	const next = $derived(lessons.find((l) => !p?.lessons[l.id]));
+	const due = $derived(progress.loaded ? progress.due(code).length : 0);
+	const dailyScore = $derived(p?.daily[dayKey()]);
+	const challenges = $derived(MODES.filter((m) => m.group === 'challenge'));
+	const bestOf = (mode: string) => p?.bests[mode];
+</script>
+
+<a
+	href={resolve('/projects/language-learner')}
+	class="mb-6 inline-flex items-center gap-1 text-sm ll-muted hover:text-[var(--site-text)]"
+	><ArrowLeft size={14} aria-hidden="true" /> language learner</a
+>
+
+<header class="mb-8 flex flex-wrap items-end justify-between gap-4">
+	<div>
+		<h1 class="text-4xl font-semibold tracking-tight sm:text-5xl">{course.name}</h1>
+		<p class="mt-2 text-lg ll-muted">
+			<span lang={code}>{course.nativeName}</span> ·
+			<span lang={course.glossLang}>{course.tagline}</span>
+		</p>
+	</div>
+	{#if progress.loaded}
+		<div class="flex flex-wrap gap-2">
+			<span class="ll-pill"
+				><Flame size={14} aria-hidden="true" /> {progress.streak(code)} day streak</span
+			>
+			<span class="ll-pill">{progress.todayXp(code)} XP today</span>
+			<span class="ll-pill">{p?.xp ?? 0} XP total</span>
+		</div>
+	{/if}
+</header>
+
+<section class="mb-12 grid gap-4 md:grid-cols-2" aria-label="Up next">
+	<div class="ll-card flex flex-col justify-between gap-4">
+		{#if next}
+			<div>
+				<p class="text-sm ll-muted">
+					{p && Object.keys(p.lessons).length ? 'next lesson' : 'start here'}
+				</p>
+				<h2 class="text-2xl font-semibold" lang={code}>{next.title}</h2>
+				<p class="ll-muted">{next.summary}</p>
+			</div>
+			<a
+				href={resolve('/projects/language-learner/[lang]/lesson/[lesson]', {
+					lang: code,
+					lesson: next.id
+				})}
+				class="ll-button self-start">Start lesson</a
+			>
+		{:else}
+			<div>
+				<p class="text-sm ll-muted">course complete</p>
+				<h2 class="text-2xl font-semibold">Every lesson done</h2>
+				<p class="ll-muted">Keep your words fresh with reviews and challenges.</p>
+			</div>
+		{/if}
+	</div>
+	<div class="ll-card flex flex-col justify-between gap-4">
+		<div>
+			<p class="text-sm ll-muted">reviews</p>
+			<h2 class="text-2xl font-semibold">{due} due</h2>
+			<p class="ll-muted">
+				{#if !p || !Object.keys(p.cards).length}
+					Words from finished lessons show up here when it's time to repeat them.
+				{:else if due}
+					Spaced repetition: review now to keep them.
+				{:else}
+					Nothing due. You can still practise your weakest words.
+				{/if}
+			</p>
+		</div>
+		<a
+			href={resolve('/projects/language-learner/[lang]/practice/[mode]', {
+				lang: code,
+				mode: 'review'
+			})}
+			class="ll-button self-start {due ? '' : 'll-button-quiet'}">Review</a
+		>
+	</div>
+</section>
+
+<section class="mb-12" aria-labelledby="challenges">
+	<div class="mb-4 flex flex-wrap items-end justify-between gap-3">
+		<h2 id="challenges" class="text-2xl font-semibold">challenges</h2>
+		<a
+			href={resolve('/projects/language-learner/[lang]/words', { lang: code })}
+			class="text-sm ll-muted underline underline-offset-2 hover:text-[var(--site-text)]"
+			>all words</a
+		>
+	</div>
+	<div class="grid gap-3 sm:grid-cols-2 lg:grid-cols-4">
+		{#each challenges as m (m.id)}
+			<a
+				href={resolve('/projects/language-learner/[lang]/practice/[mode]', {
+					lang: code,
+					mode: m.id
+				})}
+				class="ll-card"
+			>
+				<h3 class="font-semibold">{m.title}</h3>
+				<p class="text-sm ll-muted">{m.description}</p>
+				<p class="mt-2 text-sm">
+					{#if m.id === 'daily'}
+						{#if dailyScore !== undefined}<span class="ll-done">done today · {dailyScore}%</span
+							>{:else}not done yet{/if}
+					{:else if bestOf(m.id) !== undefined}
+						best: {bestOf(m.id)}
+					{/if}
+				</p>
+			</a>
+		{/each}
+	</div>
+	<h3 class="mt-8 mb-3 text-lg font-semibold">endless drills</h3>
+	<div class="grid gap-3 sm:grid-cols-2 lg:grid-cols-3">
+		{#each data.drills as d (d.id)}
+			{@const skill = Object.entries(p?.skills ?? {}).filter(
+				([k]) => k === d.id || k.startsWith(d.id + '-')
+			)}
+			{@const seen = skill.reduce((n, [, s]) => n + s.seen, 0)}
+			{@const right = skill.reduce((n, [, s]) => n + s.right, 0)}
+			<a
+				href={resolve('/projects/language-learner/[lang]/practice/[mode]', {
+					lang: code,
+					mode: `drill-${d.id}`
+				})}
+				class="ll-card"
+			>
+				<h4 class="font-semibold">{d.title}</h4>
+				<p class="text-sm ll-muted">{d.description}</p>
+				{#if seen}<p class="mt-2 text-sm">
+						{seen} answered · {Math.round((right / seen) * 100)}% right
+					</p>{/if}
+			</a>
+		{/each}
+	</div>
+</section>
+
+<section aria-labelledby="levels">
+	<h2 id="levels" class="mb-4 text-2xl font-semibold">lessons</h2>
+	<div class="space-y-10">
+		{#each course.levels as lv (lv.id)}
+			{@const done = lv.lessons.filter((l) => p?.lessons[l.id]).length}
+			<div>
+				<div class="mb-3 flex flex-wrap items-end justify-between gap-3">
+					<div>
+						<h3 class="text-xl font-semibold">
+							<span class="ll-badge mr-2">{lv.band}</span>{lv.title}
+						</h3>
+						<p class="text-sm ll-muted">{lv.description}</p>
+					</div>
+					<div class="flex items-center gap-3">
+						<span class="text-sm ll-muted">{done}/{lv.lessons.length}</span>
+						<a
+							href={resolve('/projects/language-learner/[lang]/practice/[mode]', {
+								lang: code,
+								mode: `test-${lv.id}`
+							})}
+							class="ll-chip">{done === lv.lessons.length ? 'Level test' : 'Test out'}</a
+						>
+					</div>
+				</div>
+				<div class="mb-3">
+					<ProgressBar value={done} max={lv.lessons.length} label="{lv.band} progress" small />
+				</div>
+				<ol class="grid gap-2 md:grid-cols-2">
+					{#each lv.lessons as lesson, i (lesson.id)}
+						{@const record = p?.lessons[lesson.id]}
+						<li>
+							<a
+								href={resolve('/projects/language-learner/[lang]/lesson/[lesson]', {
+									lang: code,
+									lesson: lesson.id
+								})}
+								class="ll-card flex items-center gap-3 !p-3"
+							>
+								<span
+									class="ll-lesson-dot"
+									class:is-done={record}
+									class:is-next={next?.id === lesson.id}
+								>
+									{#if record}<Check size={16} aria-label="done" />{:else}{i + 1}{/if}
+								</span>
+								<span class="min-w-0 flex-1">
+									<span class="block truncate font-medium" lang={code}>{lesson.title}</span>
+									<span class="block truncate text-sm ll-muted">{lesson.summary}</span>
+								</span>
+								{#if record}<span class="text-sm ll-muted">{record.best}%</span>{/if}
+							</a>
+						</li>
+					{/each}
+				</ol>
+			</div>
+		{/each}
+	</div>
+</section>

src/routes/projects/language-learner/[lang]/+page.ts

@@ -0,0 +1,11 @@
+import type { PageLoad } from './$types';
+
+export const load: PageLoad = async ({ parent }) => {
+	const { course } = await parent();
+	return {
+		seo: {
+			title: `Learn ${course.name} · Language Learner`,
+			description: `${course.name} lessons from ${course.levels[0].band} to ${course.levels.at(-1)!.band}, with spaced repetition and endless daily challenges.`
+		}
+	};
+};

src/routes/projects/language-learner/[lang]/lesson/[lesson]/+page.svelte

@@ -0,0 +1,173 @@
+<script lang="ts">
+	import { resolve } from '$app/paths';
+	import { onMount } from 'svelte';
+	import ArrowLeft from 'lucide-svelte/icons/arrow-left';
+	import ArrowRight from 'lucide-svelte/icons/arrow-right';
+	import { lessonSession } from '$lib/language-learner/exercises';
+	import { romanize } from '$lib/language-learner/hangul';
+	import { progress } from '$lib/language-learner/progress.svelte';
+	import { seeded } from '$lib/language-learner/random';
+	import { hasVoice } from '$lib/language-learner/speech';
+	import type { Exercise, SessionResult } from '$lib/language-learner/types';
+	import Results from '$lib/language-learner/ui/Results.svelte';
+	import Session from '$lib/language-learner/ui/Session.svelte';
+	import Speak from '$lib/language-learner/ui/Speak.svelte';
+
+	let { data } = $props();
+	const course = $derived(data.course);
+	const lesson = $derived(data.lesson);
+	const code = $derived(course.code);
+
+	let voice = $state(false);
+	let queue = $state<Exercise[] | null>(null);
+	let result = $state<SessionResult | null>(null);
+	let run = $state(0);
+	const audio = $derived(voice && progress.settings.audio);
+	const record = $derived(
+		progress.loaded ? progress.data.langs[code]?.lessons[lesson.id] : undefined
+	);
+	const showRoman = $derived(code === 'ko' && progress.settings.romanization);
+
+	onMount(async () => {
+		voice = await hasVoice(course.voice);
+	});
+
+	// Reset when navigating between lessons.
+	$effect(() => {
+		void lesson.id;
+		queue = null;
+		result = null;
+	});
+
+	function start() {
+		queue = lessonSession(course, lesson, seeded(`${lesson.id}:${Date.now()}`), {
+			typing: progress.typing(code),
+			audio
+		});
+		result = null;
+		run++;
+		scrollTo({ top: 0 });
+	}
+
+	function finish(r: SessionResult) {
+		queue = null;
+		if (r.reason !== 'done') return;
+		const score = Math.round((r.firstTry / Math.max(1, r.total)) * 100);
+		const bonus = 10 + (score === 100 ? 5 : 0);
+		progress.completeLesson(code, lesson.id, score, [...lesson.words, ...lesson.sentences]);
+		progress.addXp(code, bonus);
+		result = { ...r, xp: r.xp + bonus };
+		scrollTo({ top: 0 });
+	}
+</script>
+
+{#if queue}
+	{#key run}
+		<Session {course} {queue} requeue {audio} onfinish={finish} />
+	{/key}
+{:else}
+	<a
+		href={resolve('/projects/language-learner/[lang]', { lang: code })}
+		class="mb-6 inline-flex items-center gap-1 text-sm ll-muted hover:text-[var(--site-text)]"
+		><ArrowLeft size={14} aria-hidden="true" /> {course.name}</a
+	>
+
+	{#if result}
+		<Results
+			{result}
+			{code}
+			glossLang={course.glossLang}
+			title="Lesson complete"
+			subtitle={lesson.title}
+			score={Math.round((result.firstTry / Math.max(1, result.total)) * 100)}
+			percent
+		>
+			<button type="button" class="ll-button ll-button-quiet" onclick={start}>Practise again</button
+			>
+			{#if data.next}
+				<a
+					href={resolve('/projects/language-learner/[lang]/lesson/[lesson]', {
+						lang: code,
+						lesson: data.next.id
+					})}
+					class="ll-button">Next: {data.next.title} <ArrowRight size={16} aria-hidden="true" /></a
+				>
+			{:else}
+				<a href={resolve('/projects/language-learner/[lang]', { lang: code })} class="ll-button"
+					>Back to {course.name}</a
+				>
+			{/if}
+		</Results>
+	{/if}
+
+	<header class="mb-8 flex flex-wrap items-end justify-between gap-4">
+		<div>
+			<p class="mb-1 text-sm ll-muted">
+				<span class="ll-badge mr-2">{data.level.band}</span>{data.level.title}
+			</p>
+			<h1 class="text-3xl font-semibold tracking-tight sm:text-4xl" lang={code}>{lesson.title}</h1>
+			<p class="mt-1 text-lg ll-muted">{lesson.summary}</p>
+		</div>
+		<div class="flex items-center gap-3">
+			{#if record}<span class="text-sm ll-muted">best {record.best}% · {record.runs}×</span>{/if}
+			<button type="button" class="ll-button" onclick={start}
+				>{record ? 'Practise' : 'Start lesson'}</button
+			>
+		</div>
+	</header>
+
+	<div class="grid gap-10 lg:grid-cols-[minmax(0,3fr)_minmax(0,2fr)]">
+		<article class="ll-notes prose" lang={course.glossLang}>
+			<!-- eslint-disable-next-line svelte/no-at-html-tags -- trusted course content -->
+			{@html data.notesHtml}
+		</article>
+
+		<aside class="space-y-8">
+			<section>
+				<h2 class="mb-3 text-lg font-semibold">
+					{lesson.words.some((w) => w.kind === 'script') ? 'letters and words' : 'words'}
+				</h2>
+				<ul class="divide-y divide-[var(--site-border)] border-y border-[var(--site-border)]">
+					{#each lesson.words as w (w.id)}
+						<li class="flex items-center gap-3 py-2">
+							<span class="min-w-0 flex-1">
+								<span class="font-medium" lang={code}>{w.target.join(' / ')}</span>
+								{#if showRoman && w.kind === 'word'}<span class="ml-1 text-sm ll-muted"
+										>{romanize(w.target[0])}</span
+									>{/if}
+								<span
+									class="block text-sm ll-muted"
+									lang={w.kind === 'script' ? undefined : course.glossLang}
+									>{w.gloss.join(', ')}{w.note ? ` · ${w.note}` : ''}</span
+								>
+							</span>
+							{#if audio && (w.kind !== 'script' || /[가-힣]/.test(w.target[0]))}<Speak
+									text={w.target[0]}
+									voice={course.voice}
+								/>{/if}
+						</li>
+					{/each}
+				</ul>
+			</section>
+			{#if lesson.sentences.length}
+				<section>
+					<h2 class="mb-3 text-lg font-semibold">sentences</h2>
+					<ul class="divide-y divide-[var(--site-border)] border-y border-[var(--site-border)]">
+						{#each lesson.sentences as s (s.id)}
+							<li class="flex items-center gap-3 py-2">
+								<span class="min-w-0 flex-1">
+									<span lang={code}>{s.target[0]}</span>
+									<span class="block text-sm ll-muted" lang={course.glossLang}>{s.gloss[0]}</span>
+								</span>
+								{#if audio}<Speak text={s.target[0]} voice={course.voice} />{/if}
+							</li>
+						{/each}
+					</ul>
+				</section>
+			{/if}
+			<button type="button" class="ll-button w-full" onclick={start}
+				>{record ? 'Practise' : 'Start lesson'}</button
+			>
+		</aside>
+	</div>
+{/if}

src/routes/projects/language-learner/[lang]/lesson/[lesson]/+page.ts

@@ -0,0 +1,24 @@
+import { error } from '@sveltejs/kit';
+import { marked } from 'marked';
+import { allLessons } from '$lib/language-learner/course';
+import type { PageLoad } from './$types';
+
+export const load: PageLoad = async ({ parent, params }) => {
+	const { course } = await parent();
+	const lessons = allLessons(course);
+	const index = lessons.findIndex((l) => l.id === params.lesson);
+	if (index < 0) error(404, 'Unknown lesson');
+	const lesson = lessons[index];
+	const level = course.levels.find((lv) => lv.id === lesson.level)!;
+	return {
+		lesson,
+		level,
+		next: lessons[index + 1] ?? null,
+		// Notes are course content written in this repository, not user input.
+		notesHtml: marked.parse(lesson.notes, { async: false }),
+		seo: {
+			title: `${lesson.title} · ${course.name} ${level.band}`,
+			description: `${course.name} lesson: ${lesson.summary}. ${lesson.words.length} words with exercises.`
+		}
+	};
+};

src/routes/projects/language-learner/[lang]/practice/[mode]/+page.svelte

@@ -0,0 +1,346 @@
+<script lang="ts">
+	import { resolve } from '$app/paths';
+	import { onMount } from 'svelte';
+	import ArrowLeft from 'lucide-svelte/icons/arrow-left';
+	import { mixed, reviews, scopeOf } from '$lib/language-learner/challenges';
+	import { progress } from '$lib/language-learner/progress.svelte';
+	import { seeded, type Rng } from '$lib/language-learner/random';
+	import { hasVoice } from '$lib/language-learner/speech';
+	import { dayKey } from '$lib/language-learner/srs';
+	import type { Exercise, SessionResult } from '$lib/language-learner/types';
+	import Results from '$lib/language-learner/ui/Results.svelte';
+	import Session from '$lib/language-learner/ui/Session.svelte';
+
+	let { data } = $props();
+	const course = $derived(data.course);
+	const code = $derived(course.code);
+	const mode = $derived(data.mode);
+
+	type Setup = {
+		queue: Exercise[];
+		more?: () => Exercise | null;
+		lives?: number;
+		seconds?: number;
+		requeue?: boolean;
+		xpPer?: number;
+	};
+
+	let voice = $state(false);
+	let setup = $state<Setup | null>(null);
+	let result = $state<SessionResult | null>(null);
+	type Headline = {
+		title: string;
+		score?: number;
+		percent?: boolean;
+		record: boolean;
+		note?: string;
+	};
+	let headline = $state<Headline | null>(null);
+	let run = $state(0);
+	let drillLevel = $state(1);
+	const audio = $derived(voice && progress.settings.audio);
+	const p = $derived(progress.loaded ? progress.data.langs[code] : undefined);
+	const scopeId = $derived(p?.scope ?? '');
+	const scope = $derived(scopeOf(course, p, scopeId));
+	const mixedMode = $derived(['daily', 'sprint', 'survival', 'endless'].includes(mode.kind));
+	const bestKey = $derived(mode.kind === 'drill' ? `drill-${mode.id}` : mode.kind);
+	const best = $derived(p?.bests[bestKey]);
+	const dailyDone = $derived(mode.kind === 'daily' ? p?.daily[dayKey()] : undefined);
+	const reviewInfo = $derived(
+		mode.kind === 'review' && p
+			? reviews(course, p, progress.due(code), seeded(0), { typing: false, audio: false })
+			: null
+	);
+
+	onMount(async () => {
+		voice = await hasVoice(course.voice);
+	});
+
+	// A sensible default drill level: the highest level you've started.
+	$effect(() => {
+		if (progress.loaded && mode.kind === 'drill')
+			drillLevel = scopeOf(course, progress.data.langs[code]).level;
+	});
+
+	$effect(() => {
+		void data.mode;
+		setup = null;
+		result = null;
+	});
+
+	function start() {
+		const opts = { typing: progress.typing(code), audio };
+		const rng: Rng = mode.kind === 'daily' ? seeded(`${dayKey()}:${code}`) : seeded(Date.now());
+		const lang = progress.lang(code);
+		const drills = data.drills;
+		switch (mode.kind) {
+			case 'daily': {
+				const next = mixed({ course, scope, drills, rng, opts, p: lang });
+				setup = { queue: Array.from({ length: 20 }, next), xpPer: 3 };
+				break;
+			}
+			case 'sprint':
+				setup = {
+					queue: [],
+					more: mixed({ course, scope, drills, rng, opts, p: lang }),
+					seconds: 60,
+					xpPer: 1
+				};
+				break;
+			case 'survival':
+				setup = {
+					queue: [],
+					more: mixed({ course, scope, drills, rng, opts, p: lang, ramp: true }),
+					lives: 3
+				};
+				break;
+			case 'endless':
+				setup = { queue: [], more: mixed({ course, scope, drills, rng, opts, p: lang }) };
+				break;
+			case 'review': {
+				const r = reviews(course, lang, progress.due(code), rng, opts);
+				setup = { queue: r.queue, more: r.more, requeue: true };
+				break;
+			}
+			case 'drill': {
+				const drill = drills.find((d) => d.id === mode.id)!;
+				const level = drillLevel;
+				setup = { queue: [], more: () => drill.make({ rng, level, opts, course }) };
+				break;
+			}
+			case 'test': {
+				const lv = course.levels.find((l) => l.id === mode.level)!;
+				const next = mixed({
+					course,
+					scope: {
+						lessons: lv.lessons,
+						level: scopeOf(course, undefined, lv.id).level,
+						label: lv.band
+					},
+					drills: [],
+					rng,
+					opts
+				});
+				setup = { queue: Array.from({ length: 20 }, next), xpPer: 2 };
+				break;
+			}
+		}
+		result = null;
+		headline = null;
+		run++;
+	}
+
+	function finish(r: SessionResult) {
+		const s = setup;
+		setup = null;
+		if (!s) return;
+		const accuracy = Math.round((r.correct / Math.max(1, r.answered)) * 100);
+		switch (mode.kind) {
+			case 'daily': {
+				if (r.answered < 20) {
+					headline = {
+						title: 'Daily challenge stopped',
+						record: false,
+						note: 'Finish all 20 to record your score.'
+					};
+					break;
+				}
+				const first = p?.daily[dayKey()] === undefined;
+				progress.recordDaily(code, accuracy);
+				if (first) {
+					progress.addXp(code, 20);
+					r = { ...r, xp: r.xp + 20 };
+				}
+				headline = {
+					title: 'Daily challenge done',
+					score: accuracy,
+					percent: true,
+					record: false,
+					note: first
+						? 'Your score for today is saved. +20 XP bonus.'
+						: 'Only your first run of the day counts.'
+				};
+				break;
+			}
+			case 'sprint':
+			case 'survival':
+			case 'endless':
+			case 'drill':
+				headline = {
+					title:
+						mode.kind === 'survival'
+							? 'Out of lives'
+							: mode.kind === 'sprint'
+								? "Time's up"
+								: 'Session over',
+					score: r.correct,
+					record: r.correct > 0 && progress.recordBest(code, bestKey, r.correct)
+				};
+				break;
+			case 'review':
+				headline = { title: 'Review done', record: false };
+				break;
+			case 'test': {
+				const passed = r.answered >= 20 && accuracy >= 80;
+				const lv = course.levels.find((l) => l.id === mode.level)!;
+				if (passed)
+					for (const lesson of lv.lessons)
+						progress.completeLesson(code, lesson.id, accuracy, [
+							...lesson.words,
+							...lesson.sentences
+						]);
+				headline = {
+					title: passed ? `${lv.band} passed` : r.answered < 20 ? 'Test stopped' : 'Not yet',
+					score: accuracy,
+					percent: true,
+					record: false,
+					note: passed
+						? `Every ${lv.band} lesson is now marked as done and its words are in your reviews.`
+						: 'You need 80% on all 20 questions. The lessons will get you there.'
+				};
+				break;
+			}
+		}
+		result = r;
+	}
+</script>
+
+{#if setup}
+	{#key run}
+		<Session
+			{course}
+			queue={setup.queue}
+			more={setup.more}
+			lives={setup.lives}
+			seconds={setup.seconds}
+			requeue={setup.requeue}
+			xpPer={setup.xpPer}
+			{audio}
+			onfinish={finish}
+		/>
+	{/key}
+{:else}
+	<a
+		href={resolve('/projects/language-learner/[lang]', { lang: code })}
+		class="mb-6 inline-flex items-center gap-1 text-sm ll-muted hover:text-[var(--site-text)]"
+		><ArrowLeft size={14} aria-hidden="true" /> {course.name}</a
+	>
+
+	{#if result && headline}
+		<Results
+			{result}
+			{code}
+			glossLang={course.glossLang}
+			title={headline.title}
+			subtitle={mode.title}
+			score={headline.score}
+			percent={headline.percent}
+			record={headline.record}
+		>
+			{#if headline.note}<p class="mb-2 w-full ll-muted">{headline.note}</p>{/if}
+			<button type="button" class="ll-button" onclick={start}>Again</button>
+			<a
+				href={resolve('/projects/language-learner/[lang]', { lang: code })}
+				class="ll-button ll-button-quiet">Back to {course.name}</a
+			>
+		</Results>
+	{/if}
+
+	<header class="mb-6">
+		<h1 class="text-3xl font-semibold tracking-tight sm:text-4xl">{mode.title}</h1>
+		<p class="mt-1 text-lg ll-muted">{mode.description}</p>
+	</header>
+
+	{#if progress.loaded}
+		<div class="ll-card max-w-2xl space-y-5">
+			{#if mixedMode}
+				<div>
+					<p class="mb-2 font-semibold">Questions from</p>
+					<div class="flex flex-wrap gap-2">
+						<button
+							type="button"
+							class="ll-chip"
+							aria-pressed={scopeId === ''}
+							onclick={() => {
+								progress.lang(code).scope = '';
+								progress.save();
+							}}>What I have learned</button
+						>
+						{#each course.levels as lv (lv.id)}
+							<button
+								type="button"
+								class="ll-chip"
+								aria-pressed={scopeId === lv.id}
+								onclick={() => {
+									progress.lang(code).scope = lv.id;
+									progress.save();
+								}}>{lv.band}</button
+							>
+						{/each}
+						<button
+							type="button"
+							class="ll-chip"
+							aria-pressed={scopeId === 'all'}
+							onclick={() => {
+								progress.lang(code).scope = 'all';
+								progress.save();
+							}}>Everything</button
+						>
+					</div>
+					<p class="mt-2 text-sm ll-muted">
+						{scope.lessons.length} lessons: {scope.lessons
+							.slice(0, 4)
+							.map((l) => l.title)
+							.join(', ')}{scope.lessons.length > 4 ? ', …' : ''}
+					</p>
+				</div>
+			{/if}
+
+			{#if mode.kind === 'drill'}
+				<div>
+					<p class="mb-2 font-semibold">Difficulty</p>
+					<div class="flex flex-wrap gap-2">
+						{#each [1, 2, 3, 4, 5] as n (n)}
+							<button
+								type="button"
+								class="ll-chip"
+								aria-pressed={drillLevel === n}
+								onclick={() => (drillLevel = n)}>{['A1', 'A2', 'B1', 'B2', 'C1'][n - 1]}</button
+							>
+						{/each}
+					</div>
+				</div>
+			{/if}
+
+			{#if mode.kind === 'review' && reviewInfo}
+				<p>
+					{#if !reviewInfo.known}
+						No words to review yet. Finish a lesson first.
+					{:else}
+						<strong>{reviewInfo.due}</strong> due now, {reviewInfo.known} words learned.
+						{reviewInfo.due
+							? 'Due words come first; after that you keep practising your weakest words.'
+							: 'Nothing is due, so this practises your weakest words.'}
+					{/if}
+				</p>
+			{/if}
+
+			<div class="flex flex-wrap items-center gap-4">
+				<button
+					type="button"
+					class="ll-button"
+					disabled={mode.kind === 'review' && !reviewInfo?.known}
+					onclick={start}>Start</button
+				>
+				{#if dailyDone !== undefined}
+					<span class="ll-done">Done today: {dailyDone}%</span>
+				{:else if best !== undefined && mode.kind !== 'daily'}
+					<span class="ll-muted">Best: {best}</span>
+				{/if}
+				{#if mode.kind === 'survival' || mode.kind === 'endless' || mode.kind === 'drill'}
+					<span class="text-sm ll-muted">Endless: stop any time with ✕.</span>
+				{/if}
+			</div>
+		</div>
+	{/if}
+{/if}

src/routes/projects/language-learner/[lang]/practice/[mode]/+page.ts

@@ -0,0 +1,37 @@
+import { error } from '@sveltejs/kit';
+import { MODES } from '$lib/language-learner/modes';
+import type { PageLoad } from './$types';
+
+export type Mode =
+	| {
+			kind: 'daily' | 'sprint' | 'survival' | 'endless' | 'review';
+			title: string;
+			description: string;
+	  }
+	| { kind: 'drill'; id: string; title: string; description: string }
+	| { kind: 'test'; level: string; title: string; description: string };
+
+export const load: PageLoad = async ({ parent, params }) => {
+	const { course, drills } = await parent();
+	let mode: Mode | undefined;
+	const known = MODES.find((m) => m.id === params.mode);
+	if (known) mode = { kind: known.id, title: known.title, description: known.description };
+	const drill =
+		params.mode.startsWith('drill-') && drills.find((d) => d.id === params.mode.slice(6));
+	if (drill)
+		mode = { kind: 'drill', id: drill.id, title: drill.title, description: drill.description };
+	const level =
+		params.mode.startsWith('test-') && course.levels.find((lv) => lv.id === params.mode.slice(5));
+	if (level)
+		mode = {
+			kind: 'test',
+			level: level.id,
+			title: `${level.band} level test`,
+			description: `20 questions from ${level.band} (${level.title}). Score 80% or more to mark every ${level.band} lesson as done.`
+		};
+	if (!mode) error(404, 'Unknown practice mode');
+	return {
+		mode,
+		seo: { title: `${mode.title} · ${course.name}`, description: mode.description, index: false }
+	};
+};

src/routes/projects/language-learner/[lang]/words/+page.svelte

@@ -0,0 +1,139 @@
+<script lang="ts">
+	import { resolve } from '$app/paths';
+	import { onMount } from 'svelte';
+	import ArrowLeft from 'lucide-svelte/icons/arrow-left';
+	import { allLessons } from '$lib/language-learner/course';
+	import { romanize } from '$lib/language-learner/hangul';
+	import { progress } from '$lib/language-learner/progress.svelte';
+	import { hasVoice } from '$lib/language-learner/speech';
+	import { mastery, type Mastery } from '$lib/language-learner/srs';
+	import { normalize } from '$lib/language-learner/text';
+	import Speak from '$lib/language-learner/ui/Speak.svelte';
+
+	let { data } = $props();
+	const course = $derived(data.course);
+	const code = $derived(course.code);
+
+	type Filter = 'all' | Mastery | 'sentences';
+	let filter = $state<Filter>('all');
+	let query = $state('');
+	let voice = $state(false);
+
+	onMount(async () => {
+		voice = await hasVoice(course.voice);
+	});
+
+	const lessonTitle = $derived(new Map(allLessons(course).map((l) => [l.id, l.title])));
+	// A word taught in several lessons is listed once, under the lesson that introduces it.
+	const rows = $derived(
+		course.levels
+			.flatMap((lv) =>
+				lv.lessons.flatMap((l) =>
+					[...l.words, ...l.sentences].map((entry) => ({ entry, band: lv.band }))
+				)
+			)
+			.filter((r, i, all) => all.findIndex((x) => x.entry.id === r.entry.id) === i)
+			.map((r) => ({
+				...r,
+				mastery: mastery(progress.loaded ? progress.data.langs[code]?.cards[r.entry.id] : undefined)
+			}))
+	);
+	const counts = $derived(
+		rows.reduce(
+			(acc, r) => {
+				if (r.entry.kind !== 'sentence') acc[r.mastery]++;
+				return acc;
+			},
+			{ new: 0, learning: 0, familiar: 0, known: 0, mastered: 0 } as Record<Mastery, number>
+		)
+	);
+	const visible = $derived.by(() => {
+		const q = normalize(query);
+		return rows.filter(
+			(r) =>
+				(filter === 'all'
+					? r.entry.kind !== 'sentence'
+					: filter === 'sentences'
+						? r.entry.kind === 'sentence'
+						: r.entry.kind !== 'sentence' && r.mastery === filter) &&
+				(!q || [...r.entry.target, ...r.entry.gloss].some((t) => normalize(t).includes(q)))
+		);
+	});
+	const filters: { id: Filter; label: string }[] = [
+		{ id: 'all', label: 'All words' },
+		{ id: 'new', label: 'New' },
+		{ id: 'learning', label: 'Learning' },
+		{ id: 'familiar', label: 'Familiar' },
+		{ id: 'known', label: 'Known' },
+		{ id: 'mastered', label: 'Mastered' },
+		{ id: 'sentences', label: 'Sentences' }
+	];
+</script>
+
+<a
+	href={resolve('/projects/language-learner/[lang]', { lang: code })}
+	class="mb-6 inline-flex items-center gap-1 text-sm ll-muted hover:text-[var(--site-text)]"
+	><ArrowLeft size={14} aria-hidden="true" /> {course.name}</a
+>
+
+<header class="mb-6">
+	<h1 class="text-3xl font-semibold tracking-tight sm:text-4xl">{course.name} words</h1>
+	<p class="mt-1 ll-muted">
+		{#each ['learning', 'familiar', 'known', 'mastered'] as const as m (m)}
+			<span class="mr-4 inline-flex items-center gap-1.5"
+				><span class="ll-mastery" data-level={m}></span>{counts[m]} {m}</span
+			>
+		{/each}
+		<span class="inline-flex items-center gap-1.5"
+			><span class="ll-mastery"></span>{counts.new} new</span
+		>
+	</p>
+</header>
+
+<div class="mb-4 flex flex-wrap items-center gap-2">
+	<input
+		class="ll-input max-w-xs"
+		type="search"
+		placeholder="Search"
+		aria-label="Search words"
+		bind:value={query}
+	/>
+	{#each filters as f (f.id)}
+		<button
+			type="button"
+			class="ll-chip"
+			aria-pressed={filter === f.id}
+			onclick={() => (filter = f.id)}>{f.label}</button
+		>
+	{/each}
+</div>
+
+<p class="mb-2 text-sm ll-muted">{visible.length} shown</p>
+<ul class="divide-y divide-[var(--site-border)] border-y border-[var(--site-border)]">
+	{#each visible.slice(0, 400) as r (r.entry.id)}
+		<li class="flex items-center gap-3 py-2">
+			<span class="ll-mastery" data-level={r.mastery} title={r.mastery}></span>
+			<span class="min-w-0 flex-1">
+				<span class="font-medium" lang={code}>{r.entry.target.join(' / ')}</span>
+				{#if code === 'ko' && progress.settings.romanization && r.entry.kind !== 'script'}
+					<span class="ml-1 text-sm ll-muted">{romanize(r.entry.target[0])}</span>
+				{/if}
+				<span
+					class="block text-sm ll-muted"
+					lang={r.entry.kind === 'script' ? undefined : course.glossLang}
+					>{r.entry.gloss.join(', ')}</span
+				>
+			</span>
+			<span class="hidden text-right text-xs ll-muted sm:block"
+				>{r.band} · {lessonTitle.get(r.entry.lesson)}</span
+			>
+			{#if voice && progress.settings.audio}<Speak
+					text={r.entry.target[0]}
+					voice={course.voice}
+				/>{/if}
+		</li>
+	{/each}
+</ul>
+{#if visible.length > 400}<p class="mt-2 text-sm ll-muted">
+		Showing the first 400. Search to narrow it down.
+	</p>{/if}

src/routes/projects/language-learner/[lang]/words/+page.ts

@@ -0,0 +1,11 @@
+import type { PageLoad } from './$types';
+
+export const load: PageLoad = async ({ parent }) => {
+	const { course } = await parent();
+	return {
+		seo: {
+			title: `${course.name} vocabulary · Language Learner`,
+			description: `Every word and sentence in the ${course.name} course, with translations.`
+		}
+	};
+};

src/routes/projects/language-learner/language-learner.css

@@ -0,0 +1,450 @@
+.ll {
+	--ll-right: #3fb872;
+	--ll-right-bg: rgba(63, 184, 114, 0.12);
+	--ll-wrong: #e5645c;
+	--ll-wrong-bg: rgba(229, 100, 92, 0.12);
+	--ll-gold: #e8b64c;
+}
+
+:root[data-theme='light'] .ll {
+	--ll-right: #16804a;
+	--ll-right-bg: rgba(22, 128, 74, 0.08);
+	--ll-wrong: #c23a33;
+	--ll-wrong-bg: rgba(194, 58, 51, 0.08);
+	--ll-gold: #a86f00;
+}
+
+.ll :lang(ko) {
+	font-family: 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', var(--font-body), sans-serif;
+	word-break: keep-all;
+}
+
+.ll-card {
+	border: 1px solid var(--site-border);
+	border-radius: 0.75rem;
+	background: var(--site-surface);
+	padding: 1.25rem;
+}
+
+a.ll-card:hover,
+button.ll-card:hover:not(:disabled) {
+	background: var(--site-hover);
+}
+
+.ll-button {
+	display: inline-flex;
+	align-items: center;
+	justify-content: center;
+	gap: 0.4rem;
+	border-radius: 0.5rem;
+	background: var(--site-text);
+	color: var(--site-bg);
+	padding: 0.55rem 1.1rem;
+	font-weight: 600;
+	white-space: nowrap;
+}
+.ll-button:hover:not(:disabled) {
+	opacity: 0.85;
+}
+.ll-button:disabled {
+	opacity: 0.35;
+	cursor: not-allowed;
+}
+.ll-button-quiet {
+	background: transparent;
+	color: var(--site-text);
+	border: 1px solid var(--site-border);
+}
+.ll-button-quiet:hover:not(:disabled) {
+	background: var(--site-hover);
+	opacity: 1;
+}
+
+.ll-icon-button,
+.ll-speak {
+	display: inline-flex;
+	align-items: center;
+	justify-content: center;
+	color: var(--site-muted);
+	border-radius: 999px;
+}
+.ll-icon-button {
+	width: 2.25rem;
+	height: 2.25rem;
+}
+.ll-speak {
+	width: 1.9rem;
+	height: 1.9rem;
+	vertical-align: middle;
+}
+.ll-icon-button:hover,
+.ll-speak:hover {
+	color: var(--site-text);
+	background: var(--site-hover);
+}
+
+.ll-pill {
+	display: inline-flex;
+	align-items: center;
+	gap: 0.3rem;
+	border: 1px solid var(--site-border);
+	border-radius: 999px;
+	padding: 0.15rem 0.6rem;
+	font-size: 0.8125rem;
+	color: var(--site-muted);
+	white-space: nowrap;
+}
+.ll-combo {
+	color: var(--ll-gold);
+	border-color: var(--ll-gold);
+}
+.ll-heart {
+	color: var(--ll-wrong);
+	fill: var(--ll-wrong);
+}
+.ll-heart-lost {
+	opacity: 0.3;
+}
+
+.ll-chip {
+	display: inline-flex;
+	align-items: center;
+	gap: 0.4rem;
+	border: 1px solid var(--site-border);
+	border-radius: 999px;
+	padding: 0.3rem 0.8rem;
+	font-size: 0.875rem;
+	color: var(--site-muted);
+}
+.ll-chip:hover:not(:disabled) {
+	background: var(--site-hover);
+	color: var(--site-text);
+}
+.ll-chip[aria-pressed='true'] {
+	border-color: var(--site-text);
+	color: var(--site-text);
+}
+
+.ll-muted {
+	color: var(--site-muted);
+}
+
+.ll-badge {
+	display: inline-flex;
+	align-items: center;
+	justify-content: center;
+	min-width: 2.25rem;
+	border-radius: 0.4rem;
+	border: 1px solid var(--site-border);
+	padding: 0.1rem 0.4rem;
+	font-size: 0.75rem;
+	font-weight: 600;
+	letter-spacing: 0.04em;
+	color: var(--site-muted);
+}
+
+.ll-done {
+	color: var(--ll-right);
+}
+
+/* session */
+.ll-session {
+	max-width: 42rem;
+	margin: 0 auto;
+}
+.ll-session-top {
+	display: flex;
+	align-items: center;
+	gap: 0.75rem;
+	margin-bottom: 2rem;
+}
+.ll-stat-line {
+	font-size: 0.875rem;
+	color: var(--site-muted);
+}
+.ll-exercise {
+	min-height: 18rem;
+}
+.ll-instruction {
+	font-size: 0.875rem;
+	text-transform: uppercase;
+	letter-spacing: 0.06em;
+	color: var(--site-muted);
+	margin-bottom: 1rem;
+}
+.ll-prompt {
+	margin-bottom: 1.5rem;
+}
+.ll-prompt-text {
+	font-size: 1.75rem;
+	font-weight: 600;
+	line-height: 1.3;
+}
+.ll-roman {
+	display: block;
+	font-size: 0.875rem;
+	font-weight: 400;
+	color: var(--site-muted);
+}
+.ll-context {
+	margin-top: 0.5rem;
+	color: var(--site-muted);
+}
+.ll-hint {
+	font-size: 0.8125rem;
+	color: var(--site-muted);
+}
+.ll-listen {
+	display: inline-flex;
+	align-items: center;
+	justify-content: center;
+	width: 5rem;
+	height: 5rem;
+	border-radius: 1rem;
+	background: var(--site-text);
+	color: var(--site-bg);
+}
+.ll-slow {
+	margin-left: 0.75rem;
+	font-size: 0.875rem;
+	color: var(--site-muted);
+	text-decoration: underline;
+	text-underline-offset: 3px;
+}
+
+.ll-options {
+	display: grid;
+	gap: 0.6rem;
+}
+@media (min-width: 640px) {
+	.ll-options {
+		grid-template-columns: 1fr 1fr;
+	}
+	.ll-options.ll-options-wide {
+		grid-template-columns: 1fr;
+	}
+}
+.ll-option {
+	display: flex;
+	align-items: center;
+	gap: 0.75rem;
+	width: 100%;
+	border: 1px solid var(--site-border);
+	border-radius: 0.6rem;
+	padding: 0.75rem 1rem;
+	text-align: left;
+	font-size: 1.0625rem;
+	background: var(--site-bg);
+	transition: background 0.1s;
+}
+.ll-option:hover:not(:disabled) {
+	background: var(--site-hover);
+}
+.ll-option kbd {
+	font-family: var(--font-mono);
+	font-size: 0.75rem;
+	color: var(--site-muted);
+	border: 1px solid var(--site-border);
+	border-radius: 0.3rem;
+	padding: 0 0.35rem;
+}
+.ll-option.is-glyph span {
+	font-size: 1.75rem;
+	line-height: 1.2;
+}
+.ll-option.is-right {
+	border-color: var(--ll-right);
+	background: var(--ll-right-bg);
+}
+.ll-option.is-wrong {
+	border-color: var(--ll-wrong);
+	background: var(--ll-wrong-bg);
+}
+.ll-option.is-dim {
+	opacity: 0.5;
+}
+.ll-option.is-selected {
+	border-color: var(--site-text);
+}
+.ll-option.is-matched {
+	border-color: var(--ll-right);
+	background: var(--ll-right-bg);
+	opacity: 0.5;
+}
+
+.ll-type {
+	display: flex;
+	gap: 0.5rem;
+	margin-bottom: 0.5rem;
+}
+.ll-type input,
+.ll-input {
+	flex: 1;
+	min-width: 0;
+	border: 1px solid var(--site-border);
+	border-radius: 0.5rem;
+	background: var(--site-bg);
+	padding: 0.65rem 0.9rem;
+	font-size: 1.125rem;
+}
+.ll-input {
+	font-size: 1rem;
+	padding: 0.45rem 0.75rem;
+}
+
+.ll-build-line {
+	display: flex;
+	flex-wrap: wrap;
+	align-items: center;
+	gap: 0.5rem;
+	min-height: 3.5rem;
+	border-bottom: 2px solid var(--site-border);
+	padding: 0.5rem 0;
+	margin-bottom: 1rem;
+}
+.ll-bank {
+	display: flex;
+	flex-wrap: wrap;
+	gap: 0.5rem;
+	margin-bottom: 1.25rem;
+}
+.ll-tile {
+	border: 1px solid var(--site-border);
+	border-bottom-width: 3px;
+	border-radius: 0.5rem;
+	background: var(--site-bg);
+	padding: 0.35rem 0.8rem;
+	font-size: 1.0625rem;
+}
+.ll-tile:hover:not(:disabled) {
+	background: var(--site-hover);
+}
+.ll-tile.is-used {
+	visibility: hidden;
+}
+.ll-actions {
+	display: flex;
+	justify-content: flex-end;
+}
+
+.ll-match {
+	display: grid;
+	grid-template-columns: 1fr 1fr;
+	gap: 0.6rem;
+}
+.ll-match > div {
+	display: grid;
+	gap: 0.6rem;
+	align-content: start;
+}
+.ll-match.is-shaking {
+	animation: ll-shake 0.3s;
+}
+@keyframes ll-shake {
+	25% {
+		transform: translateX(-4px);
+	}
+	75% {
+		transform: translateX(4px);
+	}
+}
+
+.ll-feedback {
+	display: flex;
+	align-items: center;
+	justify-content: space-between;
+	gap: 1rem;
+	margin-top: 1.5rem;
+	border-radius: 0.75rem;
+	padding: 1rem 1.25rem;
+	border: 1px solid;
+}
+.ll-feedback.is-right {
+	border-color: var(--ll-right);
+	background: var(--ll-right-bg);
+	color: var(--ll-right);
+}
+.ll-feedback.is-wrong {
+	border-color: var(--ll-wrong);
+	background: var(--ll-wrong-bg);
+	color: var(--ll-wrong);
+}
+.ll-feedback p {
+	overflow-wrap: anywhere;
+}
+.ll-explain {
+	margin-top: 0.25rem;
+	color: var(--site-text);
+	font-size: 0.9375rem;
+}
+.ll-keys {
+	margin-top: 2rem;
+	text-align: center;
+	font-size: 0.75rem;
+	color: var(--site-muted);
+}
+@media (hover: none) {
+	.ll-keys,
+	.ll-option kbd {
+		display: none;
+	}
+}
+
+/* lesson notes */
+.ll-notes {
+	--tw-prose-body: var(--site-text);
+	--tw-prose-headings: var(--site-text);
+	--tw-prose-bold: var(--site-text);
+	--tw-prose-bullets: var(--site-muted);
+	--tw-prose-th-borders: var(--site-border);
+	--tw-prose-td-borders: var(--site-border);
+	--tw-prose-code: var(--site-text);
+	max-width: none;
+}
+.ll-notes table {
+	display: block;
+	overflow-x: auto;
+}
+
+/* level path */
+.ll-lesson-dot {
+	display: inline-flex;
+	align-items: center;
+	justify-content: center;
+	flex-shrink: 0;
+	width: 2rem;
+	height: 2rem;
+	border-radius: 999px;
+	border: 1px solid var(--site-border);
+	font-size: 0.8125rem;
+	color: var(--site-muted);
+}
+.ll-lesson-dot.is-done {
+	border-color: var(--ll-right);
+	background: var(--ll-right-bg);
+	color: var(--ll-right);
+}
+.ll-lesson-dot.is-next {
+	border-color: var(--site-text);
+	color: var(--site-text);
+}
+
+.ll-mastery {
+	display: inline-block;
+	width: 0.6rem;
+	height: 0.6rem;
+	border-radius: 999px;
+	background: var(--site-border);
+}
+.ll-mastery[data-level='learning'] {
+	background: var(--ll-wrong);
+}
+.ll-mastery[data-level='familiar'] {
+	background: var(--ll-gold);
+}
+.ll-mastery[data-level='known'] {
+	background: #5aa0e0;
+}
+.ll-mastery[data-level='mastered'] {
+	background: var(--ll-right);
+}

src/routes/sitemap.xml/+server.ts

@@ -2,6 +2,7 @@ import { db } from '$lib/server/db';
 import { blogArticles } from '$lib/server/db/schema';
 import { SITE_ORIGIN } from '$lib/seo';
 import { races } from '$lib/derby/races';
+import { COURSES } from '$lib/language-learner/courses';
 import { eq } from 'drizzle-orm';
 import type { RequestHandler } from './$types';
 
@@ -14,7 +15,9 @@ const staticPaths = [
 	'/projects/animaldex',
 	'/projects/derby',
 	'/projects/spotify-beatmap-finder',
-	'/projects/world-opinions'
+	'/projects/world-opinions',
+	'/projects/language-learner',
+	...COURSES.map((c) => `/projects/language-learner/${c.code}`)
 ];
 
 function escapeXml(value: string): string {