他在做什么用英语表达为：What is he doing.
doing：
1、v. 做；干（do的ing形式）
2、n. 活动；所作所为
相关介绍
双语例句：
1.你上次见到他时他在做什么？
What was he doing when you last set eyes on him?
2.他很清楚他在做什么。
He was alive to what he was doing.
3.她抬起一只眼皮看看他在做什么。
She lifted one eyelid to see what he was doing.
4.我们也能看到他在做什么。
And you can see what he's done.
5.我希望这个人明白他在做什么。
I hope this guy knows what he's doing.
6.有一阵子没见杰克了，不知道他在做什么。
I haven't seen Jack for a while, wonder what he's been doing.
7.我不知道，不管他在做什么，他一定想让他成为一个秘密。
I don't know, whatever he's doing, he must want it to be secret.
8.因为我想让他知道他在做什么。
Because I want him to know what he's doing.
9.我想他不知道他在做什么。
First of all, I don't think he could have known what he was doing.
10.那人是谁？他在做什么？
Who is that guy? What's he doing?
