不定式一、不定式的形式注意： 1、 进行式、完成式、被动语态2、 不定式的主语3、 和疑问词搭配的复合结构二、不定式作主语1. To give good service is our duty.2. To clean the rooms once a week is necessary.但是常用 it 作形式主语：3. It is our duty to give good service.4. It is necessary to clean the rooms once a week.三、不定式作宾语: 常见的只能加 to do 做宾语的动词有 agree, ask, beg, decide, expect, hate, hope, manage, offer, plan, pretend, promise, refuse, want, wish 等。可以接 to do 做宾语的动词有 begin, forget, learn, like, mean, prefer, remember 等。1. The children begged to come with us.2. They decided to move to shanghai immediately.3. This year we plan to expand our rice plots.但是如果做宾语的 to do 之后还要接宾补，就需要用形式宾语 it.4. Quite a lot of students find it difficult to master English.5. Do you think it possible for him to complete his studies in two years’ time?四、不定式作表语及宾语补足语主语是 what 引导的主语从句，to do 或者主语是 plan, aim, duty, suggestion, wish 等词时，常常用 to do 做表语。1. In one way, to protect forests is to keep natural balance.2. To promise too much is to promise nothing.3. To pour the waste everywhere is to pollute environment.4. The little boy’s aim was to become a physicist.5. The poor girl’s wish was to buy a pair of warm shoes.6. What the guide suggested was to make a fire.7. What he would say is to call a meeting immediately, I’m sure.to do 做宾补：8. We warned her not to do that again.9. I advised him to see a doctor immediately.10. I’d love them to come tonight.11. We know this book to be very informative.12. He expected his son to be a pianist.五、不定式作状语 to do 可以表示目的，结果，原因等。表示目的：1. He went to the USA to study English.2. He worked...
