Are they running?
Yes, they are
What are ................? They're jumping
they doing
What are they doing?
They're playing.
What ................................. ? They're swimming.
are they doing
Are they jumping?
No, they aren't
Are they sleeping?
Yes, they are.
Are they eating?
No, they aren't
What are they doing?
They're running
Are they reading?
No, they aren't