-을 수 없다 VS -을 수가 없다

[CaoMei513]

Hi everyone, just a quick question:

Is there a difference at all between -을 수 없다 and -을 수가 없다? I see the former more often of course, but I hear the latter pretty often in songs. Is there a subtle difference in meaning or something?

Thanks for any help!

[trutherous]

만야그미~ --대답하시겠어요?

그러면 내가 해 볼까요?

Well, hello CaoMei513, nice to meet you and welcome to KoreanClass101 -- I am a fellow student by the name of George.

Is there a difference at all between -을 수 없다 and -을 수가 없다?

It is my opinion and experience that these two phrases you asked about are exactly identical in meaning.

-을(future tense of some verb -example: to eat 먹다 -먹을) 수(in this case indicates ability/probability/ or likelihood) 없다(doesn't exist/is not)

-을 수 없다 - can't do such and such, or such and such is not permitted
-을 수가 없다? (same meaning but using subject particle "가")

if the phrase is used with the contrast particle "는" it would convey the meaning that "only that" couldn't be done.
먹을 수는 없다? "I/you/he can't eat (but maybe could drink or something else)"

[manyakumi]

Good explanations, George.
Thank you for the quick response.

Hello, CaoMei513, it's nice to see you here.
My name is Sean and I'm not a fellow student. lol

Since George already gave us the good answer,
I'm just going to show you some additional usages and meanings.

-을 수 없다 - can't do such and such, or such and such is not permitted
-을 수가 없다? (same meaning but using subject particle "가")

This is right.
There's no difference between two but the nuance.
Usually we add 가 in order to emphasize it.

믿을 수 없어요.
I can't believe you.

믿을 수가 없어요.
I can't (even) believe you.


Above two are the same in the meaning.
Though the second one has the nuance of "even" slightly.

if the phrase is used with the contrast particle "는" it would convey the meaning that "only that" couldn't be done.
먹을 수는 없다? "I/you/he can't eat (but maybe could drink or something else)"

Very good insight.
However, that sentence can have two meanings.

먹을 수는 없다.

I/you/he can't eat (but maybe could drink or something else)
I/you/he can't eat (should not better eat)


If you give a stress more on 는, it means the first one.

[timandyou]

Thanks for your help, George and Manyakumi,
I am sure that CaoMei513 learned a lot from both of you.
I have nothing to add on this question.

"Thank you so much~~!"
cheers,


Tim