Question Tags
Question tags are used in conversation to get a (positive) reaction from the person you are talking to. That’s not really difficult, is it? ;o)
Form
§ positive main clause → negative question tag
§ negative main clause → positive question tag
Examples
You are Tom, aren’t you?
He isn’t Joe, is he?
main clause with auxiliary verb → use auxiliary verb in question tag
You’ve got a car, haven’t you?