it took them three hours to work out the problem?改成特殊疑问句怎么改
问题描述：
it took them three hours to work out the problem?
改成特殊疑问句怎么改
答
How long did it take them to work out the problem?
答
How many hours did it take them to work out the problem
答
How long does it take them to work out the problem?
答
看你问什么啊