Infinitive 不定式的形式： to+ 动词原形 否定形式： not to do 进行式： to be doing 完成式： to have done 被动式： to be done 完成被动式 : to have been done 复合结构： for sb to do sth 不定式的形式： to+ 动词原形 否定形式： not to do 进行式： to be doing 完成式： to have done 被动式： to be done 完成被动式 : to have been done 复合结构： for sb to do sth

Study the following sentences: 1. Many of us like to listen to music. 2. He pretended not to see me in the street. 3. He seems to be eating something there. 4. Robert is said to have studied abroad, but I don’t know which country he studied in. 5. Nobody likes to be laughed at. 6. This novel is said to have been translated into several languages. 7. It’s impossible for us to finish the work now.

不定式的作用：不定式在句中可 作主语、宾语、宾语补足语、状 语、表语和定语，但不能单独作 谓语。不定式的逻辑主语有时用 “for+ 名词或代词宾格 ” 构成。

(1) 不定式作主语  To see is to believe ．眼见为实。 To say something is one thing; to do it is another. To master a foreign language calls for a great deal of memory work.  To save money now is hard for him.  It is right to give up smoking. It’s dangerous to leave the child alone at home. It is wrong to tell lies. It’s great fun to have a game after we finish a day of study at school.

(2) 不定式作宾语  He liked to read detective stories. You don’t need to wear your coat; it’s not that cold. I tried to give up smoking, but failed. He promised to go there with me.  I find it interesting to work with him ． We all think it necessary to tell him the truth. People who listen to Hawking’s lectures sometimes find it difficult to understand him. What he did made it impossible for me to be his friend.

(3) 不定式作宾语补足语  He asked me to do the work with him ． The boy persuaded his father to kick the habit.  Einstein was forced to leave his hometown. We students are not allowed to smoke. advise, permit, tell, wish, want, would like, order, encourage, require, warn, beg, forbid, cause, get … wait for, depend on, call on …  I have promised you to go to your party and I am sure to go on time. You can depend on me. His father promised him to buy a new bike.

注意： 在 (1) see, feel, hear, watch, notice, observe ， listen to, look at (2) have, 1et, make 等词后的补足语中, 不定式不带 to. 如果变成被动结构时, 必须带 to 。 1)Nor did he let his disease stop him from living the kind of life he had always dreamt of. 2)Today’s children are made to do a lot of things they are unwilling to do. 3)She is often heard to sing English songs.

(4) 不定式作定语  I have some books for you to read. Would you like something to eat? We have a lot of homework to do every day. Attention please. I have an announcement to make.  Where is the typist? I have a letter to be typed. I’ll go to the supermarket. Do you have anything to be taken?  He is looking for a room to live in ． Please give me a pen to write with / a piece of paper to write on.

 Anne was the first to realize that a disabled child could do as well as a normal child if he is treated like a normal human being. She is always the first to come and the last to leave.  (compare) The meeting to be held tomorrow is important. The bike being repaired now is mine. The building completed last year is now our library.

(5) 不定式作状语, 表示目的、原因、结果等  I came here specially to see you ． To escape the pull of the earth, a rocket must be very fast. We ran all the way so as /in order not to be late ． In order to catch the first bus, we got up early. He spoke in a loud voice so as to be heard by others.  (correction) To learn English well, a lot of practice is needed.

 We were very excited/surprised/disappointed to hear the news ． I am very glad/happy/pleased to hear it.  He was terrified at the sight of the footprint. She was happy ___ the result of the exam. A. as B. at c. of D. on  The question is difficult to answer ． The water in this river is not fit to drink. The boy doesn’t like school. His books seem heavy to carry.  The river is dangerous to swim in. B

 He hurried to the school (only) to find nobody was there, as it was Sunday.( 结果 ) The reporter was sent to interview a VIP, only to be told that the great man was ill.  Never too old to learn. He was too excited to say a word.  They were too anxious to leave.  The room is big enough to hold us ． Will you be kind enough to lead me to your teacher’s office?

(6) 不定式作表语 My job is to help the patient. His wish is to become a scientist. Our next step is to go over the new words. (7) 作独立成分 To tell (you) the truth ， I don't agree with you ． to be frank, to speak frankly, to be honest, to begin with, to start with …

(8) 不定式短语  to read books, to stand there  与疑问词 who, which, when, where, how, what 等连用, 在句中起名词作用, 可充当主语、表语、宾语等。 He didn't know what to say. How to raise enough money is a big problem. The difficulty is where to have the meeting. When to start is still unknown. Please tell me how to get to the railway station. There are so many beautiful things that I really don’t know which to buy.

(9) 不定式的复合结构： for sb to do/of sb to do  It is time for people to protect all the living things. It is necessary for us students to learn a foreign language. We think it impossible for such heavy work to be done within one day.  It’s kind of you to say so about my work. It’s foolish of him not to tell us the truth. I think it careless of me to have left the door open when I went to work.

(10) Useful sentences about the grammar  He asked to be sent to work in the countryside ．  I am pleased to be invited to talk here.  Helen had to shout to make herself heard.  You were silly not to have locked your car.  The flu is believed to be caused by a certain virus.  The purpose of new technologies is to make life easier, not to make it more difficult.  To finish the work on time, Bob turned to me for help.  The room seems to have been tidied up already.

Read aloud all the example sentences on each page.