Put the sentence in the interrogative form -> He's going to do the laundry tonight.
Answer may vary. There are more than one way to ask.
What is she going to do tomorrow?
She's going to buy a car tomorrow.
What is he going to do?
He is going to pay the bill.
What are they going to do on Thursday?
They're going to buy a house on Thrusday.
What is he going to do tomorrow morning?
He's going to study tomorrow morning.
What is she going to do?
She's going to get a new job.
What is she going to do on the weekend?
She's going to clean the house on the weekend.