The source is in English.
You don’t have to be.
Type your goal in your own language — or switch anytime with /lang —
and Ritsu teaches an English source back to you:
explanations, quizzes, even graded answers, in any of 10 languages.
The core move
An English page in. A lesson in your language out.
You set the language — the source doesn't have to.
- Step 1
Just ask in your language.
- Step 2
Ritsu teaches it back to you in yours.
- Step 3
Quizzes and grading, in your language too.
- Step 4
Key terms keep their English, so you’re never lost when the class is.
The gap
The best source is often in a language that isn't yours.
The clearest textbook, the lecture everyone recommends, the paper that finally explains it — often, it's in English. So you read at half speed, translating in your head, losing the thread every few lines. Or you settle for a thinner source in your own language. Either way, the language stands between you and the material.
It shouldn't.
Everywhere it counts
Your language, everywhere it counts.
Not just the explanation. The quizzes, the flashcards, the exercises — and the part that matters most, the AI grading your written answers and explaining what you missed.
Pick a language — watch the loop switch
Chính xác — bạn đã nêu đúng cơ chế.
The app's own menus and buttons stay in English for now — but everything Ritsu teaches is in your language.
Bilingual mode
Learn the idea. Keep the vocabulary.
Turn on bilingual mode and every concept keeps its original name — so you learn in your language without losing the words you'll be tested on.
terms kept in parens
Quang hợp (photosynthesis) biến ánh sáng thành năng lượng hóa học (chemical energy) trong lục lạp (chloroplast).
Turn on bilingual mode and every concept keeps its original name in parentheses — quang hợp (photosynthesis) — so you learn in your language without losing the words you'll be tested on.
Prefer the full picture? Read each section in your language and the original, one after the other.
Whatever you bring
Any source. Any command. Your language.
Bring any source — in any language — and run any of the ~40 commands. The source's language is just where it starts; yours is where it lands.
Questions
What people ask before they switch languages.
Ten: English, Vietnamese, French, Chinese, German, Japanese, Spanish, Portuguese, Korean, and Thai.
Stop learning in a second language.
Bring any source, ask in your own language, and learn it the way you think.