What's she doing?
She's sleeping.
What's she doing?
She's playing video games?
What's she doing?
She's sitting.
What's he doing?
He's making a jack-o-lantern.
What's it doing?
It's barking.
What are you doing?
What is he doing?
He's jumping.
What's she doing?
She's eating.
What's he doing?
He's working.
What is he doing?
He's walking. / He is walking.