must not do ~, not allowed to do ~

Beginner

15-20 min

very common

Expert Reviewed

Explanation

Expresses prohibition.

[Te-form] + はいけません / [Te-form] + はだめです

ここで煙草を吸ってはいけません。

Koko de tabako wo sutte wa ikemasen.

You must not smoke here.

触ってはだめです。

Sawatte wa dame desu.

You mustn't touch (it).

More casual: ～ちゃだめ or ～じゃだめ

～てもいいです

may do ~, it's okay to do ~

～てもいいです

may do ~, it's okay to do ~

～なければなりません

must do ~, have to do ~

～なくてもいいです

don't have to do ~, don't need to do ~

～ことができます

can do ~, be able to do ~

Learn common prohibitions: ここでタバコを吸ってはいけません (No smoking here). 走ってはいけません (No running).

JLPTBooks Editorial Team

Japanese Language Education Specialists

Last updated: Jan 15

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