"That car is my father's."
Translation:Cette voiture est celle de mon père.
What Duolingo indicates as wrong ? Grammatically I see one error : "cette voiture est celle qui est À mon père"; accent on the "à" (and accent in "père" by the way). Because here "à" is the preposition and not the verb "avoir". But more than the grammar, this turn of phrase sounds to complicated/not natural to me and also far from the english "That car is my father's."
Yeah, that's why Duolingo gives some button to press to put them. And that's why I'm asking what Duo put in red as wrong, to be able to help because, if it's not an accent problem (as I believe, since Duo is flexible on this), I don't see a grammatical problem.
But the better is to add an english with accents keyboard layout and switch to this one when working french/spanish or switch definitively to this one.