What's she doing?
She's throwing a ball.
What's she doing?
She's playing tennis.
What's he doing?
He's playing football.
What's he/she doing?
He's/She's watching TV.
What's she doing?
She's playing the piano.
What's he doing?
He's riding a bike.
What's he doing?
He's catching a ball.
What's she doing?
She's swimming.
What's she doing?
She's playing basketball.
What's she doing?
She's skateboarding.
What's she doing?
She's hitting a ball./She's playing baseball.
What's he doing?
He's kicking a ball.
What's she doing?
She's running.
What's he doing?
He's playing the guitar.