Translation guide
In Japanese, expressing prohibition depends on the situation: formal rules, direct commands, or polite requests. The most common patterns use 〜てはいけない, 〜てはならない, or the shorter 〜ちゃだめ／〜じゃだめ. For signs and written rules, 禁止 (kinshi) is standard. Learners should avoid literal translations like "prohibition" as a noun in casual speech.
Express that an action is not allowed, in everyday conversation or instructions.
Standard pattern meaning 'must not do'. Used in spoken and written Japanese. Attach to the て-form of a verb.
ここで写真を撮ってはいけません。
You must not take photos here.
More formal and written than 〜てはいけない. Often used in rules, regulations, or serious warnings.
この書類をなくしてはならない。
You must not lose this document.
Casual contraction of 〜てはいけない. 〜ちゃだめ follows て-form ending in て/で (e.g., 食べちゃだめ), 〜じゃだめ follows 〜で (e.g., 飲んじゃだめ). Common in everyday speech.
そんなことしちゃだめだよ。
You shouldn't do that.
Archaic/literary pattern meaning 'must not'. Seen on old signs or in formal writing. Attach to dictionary form.
立ち入るべからず。
No entry.
State a prohibition in official contexts, such as signs, regulations, or legal documents.
Noun meaning 'prohibition'. Often used on signs as 〜禁止 (e.g., 駐車禁止 'No Parking'). Can be used with する to mean 'prohibit'.
この公園では犬の散歩は禁止されています。
Walking dogs is prohibited in this park.
Formal written prohibition, as above. Suitable for rulebooks.
許可なく複製してはならない。
Unauthorized reproduction is prohibited.
Formal expression meaning 'to forbid (doing something)'. Used in legal or official statements.
法律は未成年の飲酒を禁じている。
The law prohibits underage drinking.
Ask someone not to do something in a polite or indirect way.
Polite request 'please do not do'. Attach to the negative stem (ない-form) of a verb.
ここでタバコを吸わないでください。
Please do not smoke here.
Even more polite request: 'Could I get you not to do...?'
大きな声を出さないでもらえますか。
Could you please not speak loudly?
Formal phrase used on signs or announcements: 'Please refrain from...'. Often preceded by a noun or 〜は.
館内での飲食はご遠慮ください。
Please refrain from eating and drinking inside the building.
Express a forceful 'Don't do that!' or 'No way!' in casual or emotional speech.
Direct, blunt command 'Don't do!'. Attach to dictionary form. Used mainly by men or in rough speech.
触るな！
Don't touch!
Colloquial prohibition: 'Don't you dare...'. Attach to dictionary form. Often used in scolding.
そんなこと言うんじゃない。
Don't say things like that.
The English noun 'prohibition' is often translated as 禁止 (kinshi), but in casual conversation, using 禁止 as a standalone noun can sound stiff. Instead, use verb patterns like 〜てはいけない or 〜ちゃだめ to express that something is not allowed.
ここで食べちゃだめだよ。
You can't eat here. (natural)
ここでの食事は禁止です。
Eating here is prohibited. (formal/written)
Both mean 'must not', but 〜てはいけない is common in everyday speech and writing, while 〜てはならない is more formal and often found in rules, regulations, or serious admonitions. In casual conversation, 〜ちゃだめ／〜じゃだめ is the most natural.
遅刻してはいけない。
You must not be late. (standard)
遅刻してはならない。
You must not be late. (formal/rule)
この部屋に入ってはいけません。
You must not enter this room.
写真を撮らないでください。
Please don't take pictures.