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
Example
ここで泳いじゃいけない
You must not swim here.
Important notes
- Word forms and particle choice depend on the pattern's role in the sentence.
Common mistakes
- Do not reorder or reshape the highlighted parts to match English word order.