Question

would you use tu or vous when talking the following person M. Bernard

Answer 1

You would use vous, since M. Bernard means Mr. Bernard, and is formal. Generally if you're addressing someone as "Mme." "M." or "Mlle.", it's formal.

Answer 2

You would use vous, since M. Bernard means Mr. Bernard, and is formal. Generally if you're addressing someone as "Mme." "M." or "Mlle.", it's formal.