Translation:He is not going to be able to swim tomorrow.
Those "não vai poder" can mean "won't have permission" too.
It's used for almost anything that prevents him from swimming.
Does "não vai conseguir" mean he won't be able to physically swim, as opposed to not having permission?
Conseguir is not about permission, is about being able/capable to swim, or even being able to pass through any situation that prevents him from swimming.
A good english verb for that is "to manage to".
I answered "He won't be ALLOWED to swim tomorrow". It was marked as wrong. Suggesting the right answer should be "...be ABLE...". The Portuguese sentence and meaning are exactly the same even though they're not in English.
Still marked wrong, despite "be allowed to" show as one of the choices when hovering over "poder" with the mouse. This needless inconsistency is tiresome.
He cannot swim tomorrow - should it be accepted? It's not exactly the same..
That would be the present: «Ele não pode nadar amanhã.», and it sounds a little strange to use the present conjugation with the word "tomorrow" in the same sentence.
"Can" can be used to refer to the present or the future in English. Grant was totally right. Because "can" it is a modal verb with no future form or infinitive form it breaks some rules. When in doubt, swap to "be able to" which is a normal verb and exists in every tense.
"He will not be allowed to swim tomorrow" marked wrong. (29/07/18) How can I distinguish between the different meanings of poder? Only by context?
Any reason why 'poder' is used instead of 'conseguir'? Are they interchangeable here?
«poder» is "can" or "may;" it can be both. «conseguir» is only "can" as in "to be able to."
If "he will not be allowed to swim tomorrow" is acceptable, why is it still marked wrong. The DL translation does not make sense. If he is able to swim today, why would he not be able to swim tomorrow. The translation should be "allowed`.