第一节 单项填空(共15小题;每小题1分,满分15分)
21.一The f1oor is dirty.Can anyone clean it?
— I do it a11 the time.
A.Don’t mention it. B.Why you? C.Not sure. D.Not me again.
22.Do not start a book unless you can see from the first few pages that it is you can easily read and understand.
A.that B.one C.the one D.that one