Hi,
In a context outside these lessons, I was asked to put the following sentence in la voix passive:
"Le conducteur n'a pas pu arrêter le train à temps."
I thought it would be straightforward and answered as follows:
"Le train n'a pas été pu arrêter à temps par le conducteur."
But this was marked as false, with the correct answer being:
"Le train n'a pas pu être arrêter à temps par le conducteur."
I don't believe the use of la voix passive with modal verbs (pouvoir, devoir, vouloir) was covered explicitly in this lesson, so I wanted to ask if you could please explain these rules, since it seems they might differ from the rules presented here.
thanks, Scott