Is he doing homework?
Yes, he is.
Is she singing?
Yes, she is.
What is he doing?
He's sleeping
What's she doing?
She's singing terribly.
What's he doing?
He's cleaning.
Is she eating?
No, she isn't
Is he making a machine?
No, he isn't
What's she doing?
She's singing terribly.
What are they doing?
They're dancing
What's he doing?
He's playing the guitar terribly.
Is he playing the trumpet?
No, he isn't.
What is he doing?
He's drinking
What are they doing?
They're walking.