〜てはいけません

Use 〜てはいけません to say that something must not be done — a clear prohibition, commonly seen in rules, signs, or a teacher's instructions.

How to form it: verb て-form + はいけません. It is also the "no" answer to the permission question 〜てもいいですか.

Because it sounds quite strong, when you want to politely ask someone not to do something, use 〜ないでください instead.

Examples

• ここでタバコを吸(す)ってはいけません。

  You must not smoke here.

• 図書館(としょかん)で話(はな)してはいけません。

  You must not talk in the library.

• この川(かわ)で泳(およ)いではいけません。

  You must not swim in this river.

Related patterns

• 〜てもいいです
• 〜ないでください
• Thể て