Typed Grammar makes small, open tools for learning languages. Readings, conjugations and grammar points are worked out and checked rather than guessed, so what you learn holds up.
type ヒンメル = ProperNoun<"ヒンメル">; type する = IrregularVerb & { dictionary: "する" }; type そうした = DemonstrativeAction<Demonstrative & "そう", する, "Ta">; type ヒンメルならそうした = ConditionalPhrase<ヒンメル, "なら", そうした>; const quote: ヒンメルならそうした = ""; // ✓
A lyrics player for the Mac that turns any song into a reading lesson, made for Chinese speakers learning Japanese.
Lyrics come with furigana and a Chinese translation side by side, and follow the song as it plays. Open any line to see its phrases, how each word is conjugated, and the grammar it uses.
Your own Codex annotates new songs, and Kotone checks every reading and conjugation it writes.
Each course teaches a language's grammar like a programming tutorial. Every example sentence is a TypeScript type, and the compiler checks it.
A conjugation or a reading is worked out from rules, and a checker recomputes it. Whether a person or a model wrote it, it has to add up.
Learn from sentences you actually meet, in songs and stories, each explained where it stands.
Every tool is open source and light: Kotone is a 550 KB download, and the courses run in your browser.