Meaning
Forbids an action in casual speech.
Formation
- Colloquial contraction: ては → ちゃ, では → じゃ
- 吸ってはいけない → 吸っちゃいけない, 飲んではいけない → 飲んじゃいけない
When to use it
- Core use
- Forbids an action in casual speech
Examples
14 sentences-
ここで泳いじゃいけない
You must not swim here.
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忘れちゃいけません
You must not forget.
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授業中は友達と話しちゃいけない
You must not chat with friends during class.
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図書館の本に名前を書いちゃいけない
You must not write your name in a library book.
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ここに自転車を止めちゃいけない
You must not park your bike here.
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熱いからまだ食べちゃいけない
It is hot, so you must not eat it yet.
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夜遅くまでゲームをしちゃいけない
You must not play games until late at night.
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この川で遊んじゃいけない
You must not play in this river.
6 more examples
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子どもはお酒を飲んじゃいけない
Children must not drink alcohol.
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廊下を走っちゃいけない
You must not run in the corridor.
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ここでたばこを吸っちゃいけない
You must not smoke here.
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パスワードを人に教えちゃいけない
You must not tell other people your password.
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大事な手紙を捨てちゃいけない
You must not throw away important letters.
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教室でご飯を食べちゃいけない
You must not eat in the classroom.
Important notes
- ちゃ and じゃ are casual contractions of ては and では: 吸っちゃいけない, 飲んじゃいけない. In notices and polite speech use the full てはいけません.
Common mistakes
- Keep the voicing of the て form: 飲んじゃ, not 飲んちゃ. In 読んじゃった, じゃった contracts でしまった: 読んでしまった → 読んじゃった. It does not express a prohibition.
Check yourself
Pick the translation of each sentence. The wrong options translate similar patterns, so watch the grammar rather than the words.
Similar grammar
Hear it in podcasts
The pattern appears in these episodes. They open in the app with the transcript and translation.
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