禁止を表す「じゃない」と「んじゃない」


途中で投げ出すじゃない

途中で投げ出すんじゃない

If I want to use the phrase "じゃない" to mean "don't give up", "don't ..." which
one sounds better and why? Or, their are acceptable in different context?

p.s. I know "(ん)じゃない(禁止)" is imperative and fairly colloquial.




Well, I'd like to say that the first sentence does not sound very natural. You
cannot add じゃない to the end of a verb. It is not grammatically correct. You
might instead say:

> 途中で投げ出さない  
>  Not give up.

But this sounds like a statement. It's emotionless. The english translation is
pretty accurate here. "Not give up" just sounds like a narrative statement.
The emphatic/explanatory [の allows you to give commands, give reason, and add
emotion to the statement](http://maggiesensei.com/2010/09/08/request-lesson-
when-and-how-to-
use-%E3%82%93n-%E3%81%AE%E3%81%A7%E3%81%99%E2%86%92%E3%82%93%E3%81%A7%E3%81%99%EF%BC%89/).

> 途中で投げ出すんじゃない  
>  Don't give up!

Or, to make it sound more like a request, you could write this instead:

> 途中で投げ出さないでください  
>  Please don't give up.

Also, just my two cents, but I think 諦める sounds more natural here. 「諦めないで！」or
「諦めるんじゃない！」sound a lot better to my ear, but I could be mistaken because I'm
not native speaker. Also, different words might suit different contexts.

