Meaning and Usage
The word "いけない" is commonly used to express prohibition or that something is wrong or bad. It often appears in negative commands or moral judgments. It can mean "must not do" or "it's bad to do" something.
Common Contexts
You will frequently hear "いけない" in everyday speech when someone warns against an action, such as "ここでタバコを吸ってはいけない" (You must not smoke here). It also appears when expressing that a behavior is inappropriate or morally wrong.
Collocations and Patterns
- 〜てはいけない: a strong prohibition pattern meaning "must not do"
- いけないこと: "a bad or wrong thing"
- いけないよ: a softer way to say "that's not good" often used in casual speech
Register and Nuance
"いけない" is generally neutral but can be softened or strengthened depending on context. It is common in both spoken and written Japanese. It is less formal than legal or official prohibitions but very common in daily conversation.
Common Mistake
Learners sometimes confuse "いけない" with "だめ" which also means "no good" or "not allowed." While similar, "いけない" often carries a nuance of moral or social wrongness, whereas "だめ" can be more general or casual. Pay attention to context to choose the right word.