6802
When I was first learning Japanese, I learned that the explanatory form, -んです
is always constructed by conjugating the verb in short form and adding -んです,
and that the です part is never conjugated. But in more than one instance, I
have seen -んじゃない used for the explanatory form. For example:

> おはしの使い方を知らないんです。

as opposed to:

> おはしの使い方を知るんじゃないです。

What does it mean when the -です is conjugated rather than the main verb?
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2012-09-14T01:31:05.060
6801
2012-09-14T01:47:17.213
1575
question
nuances conjugations expressions
[plain form]-んじゃない
Basically, "affirmation+じゃない(です(か))?" (notice the question mark), and
"affirmation+じゃん!" (notice the exclamation mark) is an informal way to
emphasize the affirmation.

Therefore, when you hear "おはし上手じゃん!" or "この歌を歌えるじゃないか？", it means something
like "aren't you in fact good at it?" and "I thought you said you couldn't
sing it!"

The more formal way to say it is "のではないか." It's a negative question, like
"isn't it XX?" : "いいのではないか？" (isn't it great?). But it's also often used in
more colloquial situations: "いいじゃん!" (it's great, mate!)
CC BY-SA 3.0
2012-09-14T01:47:17.213
6802
2012-09-14T01:47:17.213
356
6801
answer