Did the dog bark when you arrived late last night?
No, it didn't.
Do you study English at school?
Yes, I do. / Yes, we do.
Did they enjoy the film on TV last night?
No, they didn't.
Am I reading a book?
Yes, you are.
Is he going to have dinner alone tonight?
No, he isn't.
Does Tom go to school by bus?
No, he doesn't.
Does she work in a TV studio?
No, she doesn't.
Are you playing a game?
Yes, I am.