Translation guide
The English verb "prohibit" means to formally forbid something by rule, law, or authority. In Japanese, the most common ways to express this are the verb 禁止する (kinshi suru) and the pattern 〜てはいけない (~te wa ikenai). This guide covers formal prohibitions, everyday rules, legal bans, and softer ways to say something is not allowed.
Smoking is prohibited.
You must not enter.
To state that something is officially forbidden by a rule, law, or regulation.
The standard verb for formal prohibition. Used in rules, signs, and official statements. Often seen in the passive form 禁止されている (kinshi sarete iru) to mean 'is prohibited'.
Smoking is prohibited inside this building.
The law prohibits that act.
A slightly more literary or formal verb for 'prohibit'. Often used in legal or official contexts. The passive form 禁じられている (kinjirarete iru) is common.
Pattern for explicitly stating what is prohibited. The object marked by を is the prohibited action or thing.
To tell someone that they must not do something, in daily conversation or instructions.
The most common way to say 'must not do' or 'it's not allowed'. Used in rules, warnings, and personal prohibitions. The plain form is 〜てはいけない; the polite form is 〜てはいけません.
To refer to a legal prohibition or an act being outlawed.
Also used for legal bans. Often appears as 法律で禁止されている (houritsu de kinshi sarete iru) 'prohibited by law'.
To express that something is not allowed in a softer, less direct way, often in conversation.
Polite request not to do something. Literally 'please don't do ~'. Softer than 〜てはいけません.
禁止する is the most common and neutral verb for 'prohibit'. 禁じる is slightly more literary and often used in legal or formal written contexts. In everyday speech, 禁止する or 〜てはいけない are preferred.
The law prohibits it. (neutral)
校則で携帯電話の使用を禁じている。
School rules prohibit the use of mobile phones.
The city prohibited drinking in the park.
You must not take photos here.
You shouldn't say things like that.
A more formal or written version of 〜てはいけない. Often used in rules, regulations, or serious warnings.
You must not lose this document.
An archaic or highly formal pattern meaning 'must not', seen on old signs or in literary contexts. Not used in modern speech.
Keep off the grass. (Literally: You must not enter the lawn.)
The drug is prohibited by law.
A noun meaning 'prohibition' or 'ban', often used in compound words like 禁制品 (kinseihin, prohibited goods). More formal and less common in everyday speech.
Bringing in prohibited items is strictly forbidden.
Please don't run here.
Casual way to say 'you can't do ~' or 'it's no good to do ~'. Used among friends or family. Polite form is 〜てはだめです.
You can't do that. / That's not allowed.
Means 'to refrain from'. Used in signs or announcements to politely ask people not to do something, e.g., ご遠慮ください (go-enryo kudasai) 'please refrain from ~'.
Please refrain from talking on the phone inside the building.
The regulations prohibit it. (more formal/literary)
The English verb 'forbid' can also be translated as 禁じる or 禁止する, but 'prohibit' is more formal and often impersonal. In Japanese, the same words are used for both, but context determines the nuance. For personal forbidding (e.g., 'I forbid you to go'), 〜てはいけない or 〜な (strong command) might be more natural.
You must not go. (I forbid you to go.)