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 are they going to do on Thursday?
They're going to buy a house on Thrusday.
What is she going to do on the weekend?
She's going to clean the house on the weekend.
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 he going to do?
He is going to pay the bill.