# んじゃないか/んじゃない/じゃない



## Larris

Hello everyone 

I've always been confused on this of what I've read seems to be "isn't it A?" and the colloquial version of のではない Which most times doesn't fit into what i'm hearing.  I'm honestly just not sure how to understand using this.

It just seems to be used a lot of different ways other than something is or isn't. Especially after verbs. I have learned that んじゃない can also indicate a command not to do something. But then I encounter things like

ほとんど毎日働きすぎているうえに、1日に三時間ぐらい運動しているから、心臓が止まるんじゃないかと思った。(I overwork nearly every day, exercise for around three hours a day so I thought my heart would stop.) Why is んじゃないか being used here?

But I also read that んじゃなかった can also mean something you thought someone would do but they did not.

Ex: 日本に行くんじゃなかった？(I thought you were supposed to go to Japan?) However I have also read if you change the verb to past tense you can state that you shouldn't have done something.. But have also seen an example of stating someone else shouldn't have done something 

Ex: 朝ご飯を食べるんじゃなかった。 (You shouldn't have eaten breakfast, you know)

So basically this confuses the world out of me and seems to have a lot of uses.  Anyone who can make sense out of any of this would be my savior. Thanks in advance.


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## SoLaTiDoberman

ん=　the more colloquial form of の
じゃ＝ the colloquial form of では
んじゃないか＝のではないか

心臓が止まるんじゃないかと思った。
＝心臓が止まるのではないかと思った。
＝I wondered if my heart were going to stop.

日本に行くんじゃなかった？
=日本に行くのではなかったのですか？
＝Didn't you go to Japan? (Didn't you say that you were going to Japan?)

朝ご飯を食べるんじゃなかった。
=朝ごはんを食べるのではなかった。
＝I shouldn't have eaten breakfast.
I strongly believe that the subject should be "I", not "you."

If the subject is "you,"
朝ごはんをたべるんじゃなかった（？）
＝朝ごはんを食べるのではなかったのですか？
＝Didn't you eat breakfast? (Didn't you say that you would eat breakfast?)


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## karlalou

Yeah, I thought （ん）じゃない＝（の）ではない simply negates the words before it, but it seems that there's more usages to it. 

Yes, it can be used in a command not to do something. Sounds as though an old teacher is talking. 

Adding か after it basically makes it interrogative.



Larris said:


> 心臓が止まるんじゃないかと思った。
> Why is んじゃないか being used here?


It means 心臓が止まるのかと思った. 
But 心臓が止まるんじゃないかと思った feels more of the speaker's emotion, worry and/or surprise.

The dictionary has only two definitions for ない of negation. It's a auxiliary verb, and one usage is to negate, and the second is to invite or propose like when you say "Why don't we (_do ~_)?" in English, just in Japanese it works without 'why'.



> Ex: 日本に行くんじゃなかった？(I thought you were supposed to go to Japan?) However I have also read if you change the verb to past tense you can state that you shouldn't have done something..


日本に行くんじゃなかった？ and 日本に行ったんじゃなかった？ could be used interchangeably, but the former is used when the speaker knows it's still a future event, and the latter is used the speaker thought you had already gone to
Japan and it's surprising to see you on that day.

'shouldn't have done'..? mm.. I don't know. I think that should be something else like 行くんじゃなかったね. Yeah, I think it needs ね.



> 朝ご飯を食べるんじゃなかった。


This doesn't have any element of tag question. To mean "You shouldn't have eaten breakfast, you know", the 'you know' part needs ね at the end. If the context tells you that someone said ～するんじゃなかった to mean someone else shouldn't have done something, don't worry, it's unusual. It sounds like the speaker is regretting as if it happened to him/her.


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## Larris

Just wanted to say the translations aren't mine. Just posted from what I've read. I was surprised as well. And thanks for the replies.

Just wanted to ask a question karlalou....



karlalou said:


> It means 心臓が止まるのかと思った.
> But 心臓が止まるんじゃないかと思った feels more of the speaker's emotion, worry and/or surprise.



I had always thought のか was used in either sentences with question words or at the end of a sentence. So not sure why it's used there. 

If it seems that 
朝ご飯を食べるんじゃなかった。

Is for oneself. What's the difference between this and using ばよかった instead for I shouldn't have? The internet really seems to have few sources about this. It's painful.


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## karlalou

Larris said:


> It means 心臓が止まるのかと思った.
> But 心臓が止まるんじゃないかと思った feels more of the speaker's emotion, worry and/or surprise.
> 
> 
> 
> I had always thought のか was used in either sentences with question words or at the end of a sentence. So not sure why it's used there.
Click to expand...

Both above sentences used のか as a kind of question. mm.. のかと思った and のだと思った can be used to mean the same thing, but のか is *inference*. のだ is basically assertion.



Larris said:


> If it seems that 朝ご飯を食べるんじゃなかった。Is for oneself. What's the difference between this and using ばよかった instead for I shouldn't have?


朝ご飯、食べるんじゃなかった。(everyday spoken word)
朝ご飯、食べなければよかった。(usual spoken or written)
朝ご飯を食べるのではなかった。(seriously written literature, rigid)
These all say exactly the same thing.


Another use of じゃない came to me.
We often say like 晴れるんじゃない? This is not asking a negative event, but a positive event. This is just a half question. I mean we say it when we are almost positive, and sounds like positive to us natives. To mean it's _not _going to be clear up, we say 晴れないんじゃない？Confusing, I thought for a moment, but it's like the English tag question, huh?

[edit to add]
んじゃないかと思った is also, I think, tag question. You thought your heart was going to stop, wasn't it.


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## frequency

Larris said:


> I had always thought のか was used in either sentences with question words or at the end of a sentence. So not sure why it's used there.


Good. But you're a bit confusing.

Will he come?
↓
I asked if/whether he will come.
彼は来るのか？
彼は来るのか（どうか）聞いた。
They're question and interrogation. And the second one is a clause + interrogation (Reported speech).

Your 心臓's case isn't such a direct interrogative one: kind of hypothesis or _as if_. (I'm not saying it is exactly _as if_.)
Yours in the simplest form would be 心臓が止まるのかと思った.
So your OP_ I thought my heart would stop_, using would, is more accurate, if strictly speaking.
In both cases we use のか.

But you know, yours can be


SoLaTiDoberman said:


> ＝I wondered if my heart were going to stop.


 
Start from this 心臓が止まる（の）かと思った.
心臓が止まるんじゃないかと思った。 is just a casual form of 心臓が止まるのではないかと思った。
And yours is the most emphasised one, and shows your suspicion strongly.
I'd prefer 心臓が止まるかと思った, but 心臓が止まるのかと思った is okay, too.



> Ex: 日本に行くんじゃなかった？(I thought you were supposed to go to Japan?)


Yes, the speaker is confirming with you.


> Ex: 朝ご飯を食べるんじゃなかった。 (You shouldn't have eaten breakfast, you know)


Yes, you're regretting.


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## Larris

Thanks for all the replies. Reading them over and over to grasp it into my brain. I just have one last question about this and i'll stop bothering everyone 

What does んじゃないんですか imply then? For example ダニーは日本語を話せないんじゃないんですか what seems to be a ending tag question. Feels like the double at the end is mixing me up.


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## SoLaTiDoberman

ダニーは日本語を話せないんじゃないんですか=ダニーは日本語を話せるんですか
=*I thought Danny wasn't able to speak Japanese. But is that thought wrong?*
=Danny seems to speak Japanese. I'm surprised to know that. I'm surprised if it's true.
=Danny can speak Japanese in spite of my negative expectation.
=Is it true that Danny can speak Japanese?
=I'm surprised if Danny can speak Japanese. (But it seems that he can.)
=Danny seems to speak Japanese, unexpectedly.
=It's a little hard for me to believe that Danny can speak Japanese.
etc, etc.


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## Schokolade

Larris said:


> What does んじゃないんですか imply then? For example ダニーは日本語を話せないんじゃないんですか what seems to be a ending tag question.



じゃないんですか basically means 'Isn't it~?', 'It is ~~, isn't it?' or 'I suspect ~~.'

So ダニーは日本語を話せ*ない*ん*じゃないんですか* would be like:
'Danny can't speak Japanese, can he?' / 'I doubt Danny can speak Japanese.'
(implying you don't think he can speak Japanese)

Compare:
ダニーは日本語を話せ*る*ん*じゃないんですか*？
Danny can speak Japanese, can't he? / I suspect Danny can speak Japanese.
(implying you think he can speak Japanese)


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## karlalou

Interesting.

日本人：　あら、日本語、話せないんじゃ*ないん*ですか？！
外人：　え！だって、こんなの話せないうちですよ。

日本人Ａ：　あら、もしかして、日本語が話せないんじゃ*ない*ですか？（＝日本語が話せないんじゃないかしら？）
日本人Ｂ：　ああ、そうか。そうなのかもしれませんね。

日本人：　まあ！日本語、話せないんじゃ*ない*ですか！
日*系*人：　ハイ、ジツハ、アマリ、ハナセマセン……。

Actually, in a way, it's easier than English tag question. It's always confusing and scares me off to use it because it have to be opposite of the main sentence. In Japanese, it doesn't matter:
知ってるんじゃない？
知らないんじゃない？

By the way, 晴れるんでしょ？ and 晴れないんでしょ？ sound like you are asking for reassurance from someone said so.


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## frequency

I'm not going to make you confused more*, but don't forget, in yours,
（の）ではないか → casual form →　（ん）じゃないか,
as Doberman


SoLaTiDoberman said:


> ん=　the more colloquial form of の
> じゃ＝ the colloquial form of では
> んじゃないか＝のではないか


said.
んじゃないか can't be anything more important than a casual form of のではないか.
I recommend you to check ではないか, too. (This is easier to understand and I think you can find more information.)

Yes, good! When speaking only ですか in yours, it's a tag question: ダニーは日本語を話せないんじゃないん_ですか_?
ですよね？ is one of endings of tag question, too.

PS:
Notice the two are replaceable, so this is okay too: ダニーは日本語を話せないのではないですか？
*ごめん直した


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## Schokolade

karlalou said:


> 心臓が止まるんじゃないかと思った
> ない of negation. It's a *auxiliary verb*



Is it really an auxiliary verb? (You mean 助動詞 by "auxiliary verb", right?)

I think it's an i-adjective (形容詞)... You should have linked to this page instead, no?: ない【無い】の意味 - goo国語辞書

Compare:

ない is an auxiliary verb in:
読ま*ない*
来*ない*
でかけ*ない*
(can be rewritten as 読ま*ぬ*、来*ぬ*、でかけ*ぬ*)

ない is an i-adjective in:
金が*ない*
静かじゃ*ない*
止まるんじゃ*ない*
(_cannot_ be rewritten as 金がぬ、静かじゃぬ、止まるんじゃぬ)

... Am I wrong?


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## frequency

ない【無い】の意味 - goo国語辞書
［形］［文］な・し［ク］　ほんとだ。形容詞とされているね。

ではないか
これって連語なんだね。形容詞「ない」を使った連語なのかな？


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