A：Was it you who put these books on my desk? 是你把这些书放到我桌上的吗?
(比较原句：Did you put these books on my desk? )
B：Yes, it was. 是我。
A：Who was it that gave you the book? 是谁给了你这本书?
(比较原句：Who gave you the book?)
B：It was Tom. 是汤姆给我的。
A：How is it that he goes to school every day? 他每天是怎样去上学的?
(比较原句：How does he go to school every day?)
B：It is by bike. 是骑自行车去的。
A：It was Tom broke the window, wasn’t it? 是汤姆打烂窗户的，对吗?
B：Yes, it was. 是的。