can or cannot

I wanted to ask if the generalization of "can" or "cannot" from Italian / Spanish carries over to Portuguese. (Moderators, forgive me but I use Italian to help me learn Portuguese ... the "sense" is much closer than English --> Portuguese)

For example:
It can be done - si può fare ...
Can you say, "se pode faz/er?"
Se pode fumar aqui.

And what about "cannot" -- as in a person tries to, but doesn't succeed at.
For example:
My best friend just can't remain faithful to his wife.
Il mio migliore amico non riesce ad essere/rimanere fedele a sua moglie.
O meu melhor amigo não pode(?) ser fiel a sua esposa.
Perhaps there's an equivalent of riuscire to Portuguese?

Thank you for any suggestions.

PS I found an interesting discussion on the topic, but it was more a Brazil vs Portugal thread ... and a little over my head.

Erick, you can use any language for your learning here. That is what all of us do when learning a language, and the more language references you have the easier for you to learn. I use English to learn German because of the obvious link.


It can be done - si può fare ...👁 Tick :tick:

Can you say, "se pode faz/er?"
Se pode fumar aqui./ Pode-se fumar aqui.

And what about "cannot" -- as in a person tries to, but doesn't succeed at.

My best friend just can't remain faithful to his wife.
Il mio migliore amico non riesce ad essere/rimanere fedele a sua moglie.
O meu melhor amigo não pode(?) consegue ser fiel a sua esposa.

The usage of can varies according to context.Sometimes it will be poder, sometimes conseguir, sometimes permission and so on.
Whenever I think of different examples, I'll be back. Or someone else will add examples on this.

Thanks so much Vanda.
So "conseguir" is like riuscire ... I think someone told me that recently.

I just had another thought. For example in English we say:
"I can't dance. I dance with two left feet."
But in Italian it would be:
"Non so ballare." (Literally - I don't know how to dance)
Both statements are correct, but it hints that not only do I not know how to dance, but I'm not capable of it.
Would that become:
"Eu não sei dançar. Danço com duas patas a esquerdo." (As opposed to "não posso")
Obrigado!

Would that become:
"Eu não sei dançar. Danço com duas patas a esquerdo". Or: com dois pés esquerdos - as we say around here (As opposed to "não posso").

Esattamente. I can bet it applies for the same cases in Italian most of the times because of Romance language's structure.

Thanks Vanda ...

In the negative, does one always say "não se pode" ... or can one say "não pode-se ...?"