Is he playing the guitar? (1)
Yes, he is. He is playing the guitar.
Is he listening to music? (1)
No, he isn’t. He is playing the guitar.
Are they listening to music? (4)
Yes, they are. They are listening to music.
Are they watching TV? (3)
Yes, they are. They are watching TV.
Is she doing homework? (2)
Yes, she is. She is doing homework.
Is she listening to music? (2)
No, she isn’t. She is doing homework.
Are they doing homework? (3)
No, they aren’t. They are watching TV.
Are they watching TV? (4)
No, they aren’t. They are listening to music.