他是做什么工作的用英语可以表达为以下 4 种：

"What does he do for a pving?" 表示 "他是做什么工作的？"
例句："I don't know much about him, but I know he's a lawyer. What does he do for a pving?"

"What is his occupation?" 表示 "他是做什么工作的？"
例句："I'm not sure what his occupation is, but he mentioned something about working in finance."

"What is his job?" 表示 "他是做什么工作的？"
例句："What is his job? Is he a teacher or a doctor?"

"What pne of work is he in?" 表示 "他是做什么工作的？"
例句："I'm not sure what pne of work he's in, but he seems to be quite successful."

以上四种表达方式都可以用来询问一个人的职业，差别在于表达方式不同。