Are ____ a student? Yes, I am.
you
Are they hungry? (Negative form)
No, they aren't.
Is it tired? (Negative form)
No, it isn't.
Are you a doctor? (Negative form)
No, I'm not.
Is Helen sad? (Affirmative form)
Yes, he is.
Is she hungry? (Affirmative form)
Yes, she is.
Is she your friend? (Affirmative form)
Yes, she is.
Is he thin? (Affirmative form)
Yes, he is.