いけない · i-adjective
| Form | Positive | Negative |
|---|---|---|
| Dictionary | いけない | いけなくない |
| Polite | いけないです | いけなくないですalso いけなくありません |
| Past polite | いけなかったです | いけなくなかったですalso いけなくありませんでした |
| Past | いけなかった | いけなくなかった |
| Te-form | いけなくて | いけなくなくて |
| Adverbial | いけなく | |
| Conditional | いけなければ | いけなくなければ |
| Tara conditional | いけなかったら | いけなくなかったら |
Used to describe behavior or situations that are morally or socially unacceptable. Often used when scolding children or expressing disapproval.
そんなことをしてはいけません。
You mustn't do such a thing.
うそをつくのはいけないことだ。
Telling lies is wrong.
must not; should not; ought not to
Attaches to the -te form of a verb or adjective to express prohibition or strong advice against doing something.
ここで写真を撮ってはいけません。
You must not take photos here.
遅れてはいけないから、早く出よう。
We shouldn't be late, so let's leave early.
Expresses that something is not working, not acceptable, or beyond repair. Sense 4 (hopeless) is a stronger extension of this meaning.
このパソコン、もういけないみたい。
This computer seems to be no good anymore.
彼に頼んでもいけないよ。
It's no use asking him.
unfortunate; a shame; a pity
Used to express sympathy or regret about a situation. Often appears as いけないね or いけないことになった.
雨で運動会が中止だって。いけないね。
The sports day was canceled because of rain. That's a shame.
unable to drink (alcohol)
Specifically refers to being unable to handle alcohol; a set expression often used as お酒がいけない.
私はお酒がいけないんです。
I can't drink alcohol.
so as not to ...; lest ...; in case ...
Used in the pattern ...すると/してはいけないから/ので to express doing something to prevent an undesirable outcome.
忘れないようにメモしておこう。いけないからね。
Let's write it down so we don't forget. Just in case.
悪い is the general adjective for "bad," while いけない is used more specifically for scolding or expressing disapproval of behavior.
いけない is the standard Japanese expression for prohibition, while あかん is the Kansai dialect version used in casual speech.
いい means "good" or "fine," the direct opposite of いけない's sense of "bad" or "not allowed."
いけません is the polite form used in formal or polite speech, while いけない is the plain form used in casual conversation.