What it means
じゃないか is placed at the end of a sentence to seek agreement or confirmation, meaning “isn’t it?” or “don’t you think?” It can also express the speaker’s strong realization or insistence that something is true. It follows a plain predicate, including nouns, な-adjectives, い-adjectives, and verbs. The polite counterpart is commonly じゃないですか.
Usage note
じゃないか can sound forceful or emotionally strong, especially when the speaker is insisting on a point. Depending on context and intonation, it can also be understood as a negative question, so the intended meaning should be clear. The polite form じゃないですか is more suitable in respectful conversation.
How to use it
これは新しい本じゃないですか。
This is a new book, isn't it?
この部屋は静かじゃないですか。
This room is quiet, isn't it?
この料理はおいしいじゃないですか。
This dish is delicious, isn't it?
彼は約束を守るじゃないですか。
He keeps his promises, doesn't he?
これは新しい本じゃないか。
This is a new book, isn't it?
この部屋は静かじゃないか。
This room is quiet, isn't it?
この料理はおいしいじゃないか。
This dish is delicious, isn't it?
彼は約束を守るじゃないか。
He keeps his promises, doesn't he?
Example sentences
この道のほうが駅に近いじゃないか。
This road is closer to the station, isn't it?
この箱はまだ使えるじゃないか。
This box can still be used, can't it?
明日の発表は大切じゃないか。
Tomorrow's presentation is important, isn't it?
春の風は気持ちいいじゃないか。
The spring breeze feels pleasant, doesn't it?
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