Is it Okay, please?

Personally I would say "because of the lack of time".

Short time doesn't really make much sense to me?

Or you could say "because he has no/little time/not enough time"
Hope that helps.

He isn't going to finish his exam because there won't be enough time.

CJ

Yes, there are various ways in which a native speaker might express this, but "the short time" isn't one of them.

I'd probably say, "because of a [or the] lack of time", but other alternatives could include:

a. "...because of a shortage of time"

b. "...because of the short time (he has) available"

...as well as the suggestions already given in Anon's and CalifJ

Hello, Anon

Thanks for the help. So I suppose I can say:

He isn't going to finish his exams because the time is little = He isn't going to finish his exams because of the little time. (Isn't it?)

Alan.

Thank you , CalifJim.

Best wishes,
Alan

Hello yizhivika

Thanks for the alternatives.

Best wishes,
Alan

Hi Alan,

He isn't going to finish his exams because the time is little = He isn't going to finish his exams because of the little time. (Isn't it?)

No, a native speaker wouldn't say that; if you want to use the adjective little here you could use it like this:

He isn't going to finish his exams because he has too little time (available).

Thanks for helping me once more, yizhivika!

Best wishes,
Alan