5.5 助动词do 的用法
 
1) 构成一般疑问句,例如:
  Do you want to pass the CET? 你想通过大学英语测试吗?
  Did you study German? 你们学过德语吗?

2) do + not 构成否定句,例如:
  I do not want to be criticized.  我不想挨批评。
  He doesn't like to study.  他不想学习。
  In the past, many students did not know the importance of English. 过去,好多学生不知道英语的重要性。

3) 构成否定祈使句,例如:
 Don't go there. 不要去那里。
 Don't be so absent-minded. 不要这么心不在焉。
说明: 构成否定祈使句只用do,不用did和does。

4) 放在动词原形前,加强该动词的语气,例如:
 Do come to my birthday party. 一定来参加我的生日宴会。
 I did go there. 我确实去那儿了。
 I do miss you. 我确实想你。

5) 用于倒装句,例如:
 Never did I hear of such a thing.  我从未听说过这样的事情。
 Only when we begin our college life do we realize the importance of English.
只有在开始大学生活时我们才认识到英语的重要性。
说明: 引导此类倒装句的副词有never, seldom, rarely, little, only, so, well等。

6) 用作代动词,例如:
 ---- Do you like Beijing? --你喜欢北京吗?
 ---- Yes, I do. --是的,喜欢。(do用作代动词,代替like Beijing.)
 He knows how to drive a car, doesn't he?
 他知道如何开车,对吧?