Salut!
Perhaps it's too awkward to put this issue on an American forum but since I know many members here aren't English native speakers... and also know that many Americans too were so kind as to answer my questions, even those most peculiar...
Well, the current idea on my mind is to watch
good samples from the oral part of the exam where the English used by the candidates is proficient indeed (C2). If anyone were so helpful as to help me to look for some... Currently, I'm doing the search myself but so far the results have not been satisfactory
.