you couldn't
In questo caso non potresti capire.
In that case you wouldn't be able to understand.
— Ghost in the Shell (1995)
Non potresti nascondermi a casa tua o qualcosa del genere, cretina?!
Couldn't you hide me at your place or something, you idiot?!
— The Garden of Sinners Chapter 5: Paradox Paradigm (2008)
Non potresti aspettare un pochino?
Couldn't you wait a little while?