Are you a girl?
No,I'm not.
Is he in the room?
No,he isn't.
Is she fifteen?
No,she isn't.
Are they friends?
NO,they aren't.
Do you have a bike?
No,I don't.
Does he have a key?
No,he doesn't.
Does the dog have four legs?
No,it doesn't.
Do they have friends?
No,they don't.