"When do you drink wine?"
Translation:Quand buvez-vous du vin ?
It gave you the informal verb and pronoun instead of the formal verb and pronoun. Certainly it is possible to construct the question from the words you provided.
Quand bois-tu du vin ? ~ informal
Quand buvez-vous du vin ? ~ formal
A previous question asked "Does he like fish" or something like that. I answered Aime-t-il du poisson, but was wrong. I should have used le instead of du. I think it is because we are talking about fish in general not any specific fish. So why isn't the answer to this question: Quand buvez-vous le vin?
Guys, I have the same problem. It doesn't give me the option and WON"T let me go further . BUT there is a symbol for keyboard and you CAN type the words (Quand buvez-vous du vin) there . Just ignore this bug....Duolingo is the best progam. I've never was ale to learn French until now ! :)