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1、1 八年级英语动词不定式用法梳理 动词不定式是由“ 不定式符号to+动词原形 ”构成的 一种非谓语动词 结构。有些 动词不定式不带 to，动词 不定式可以作句子的 主语、表语、宾语、定语、补语、 状语或单独使用 。不定式保留动词的某些特性，可以 有自己的宾语、 状语等。动词不定式和它后面的宾语、 状语等一起构成短语，叫作不定式短语。 一、用作主语 多数情况用 it 作形式主语， 把真正的主语动词不 定式置于句末，特别是不定式短语较长时。动词不定 式作主语， 谓语动词用第三人称单数形式。疑问词 + 不定式短语作主语可置于句首，复合不定式结构作主 语常置于句末。如： 1. It is our du
2、ty to try our best to deal with these problems. 2.The head teacher said it was necessary to talk with his mother. 3.How to learn English well is important. 4.To see is to believe.(眼见为实；百闻不如一见) 二、用作表语 动词不定式作表语， 常说明主语的内容、 性质、特征。 2 如： 1.The best way is to join an English club. 2.The first thing is to l
3、isten to the teacher carefully. 三、用作宾语 1.可以接带 to 的动词不定式作宾语的动词主要有：要 求选择同意 (ask, choose, agree) ，期望决定学习 (expect, hope, decide, learn)，宁可假装知道 (prefer, pretend, know)，希望想要愿意 (wish, want, would like / love) 。 如： 1)We decided to talk to some students about why they go there. 2)He prefers to eat white brea
4、d and rice. 3)Id love to visit Mexico. 2.动词 decide, know, learn, show, teach, tell.，介词结 构 on.可用疑问词带 to 的不定式短语 作宾语，但 why 后面的不定式不带to。如： 1)Could you please tell me where to park my car? 2)It gives advice on what to do in lots of different situations. 3.动词 feel, find, make, think 等后面，可以用 it 作形 式宾语代替真正的宾
5、语动词不定式，句子结构 是.feel / find / make / . it+adj. / n.+to do. 。如： 3 4. 感知动词 like, love, know等一般不用进行时态。 5.后接动词不定式或v-ing 形式作宾语，意思差别较大 的动词有 forget, remember等。后接不定式作宾语， 表动作尚未发生；后接v-ing 形式作宾语，表动作已 经发生。 stop to do停下来做另外一件事， to do 是目 的状语； stop doing停止做、不做当前这件事，doing 是宾语。try to do 尽力做，try doing 试试看；go on to do接着
6、做另外的事，go on doing继续做原来的事 。 如： 1)When I left home, I forgot to bring it with me. 2)I stopped using them last year. 四、用作定语 1.句子的主语或宾语是动词不定式的逻辑主语，不定 式与其所修饰的名词、代词等存在逻辑的动宾关系 . 1)I have so many clothes to wash today. 2)I cant think of any good advice to give her. 3)We have no houses to live in. 2.动词不定式所修饰
7、的名词是place, time, way等时， 不定式与这些名词呈现出动状关系 或同位关系 。如： 1)He needs time to do homework. 2) He wants to know the best way to travel around the city. 4 3.在“there be.”句型里，句子的主语是动词不定式 动作的对象： 1) Theres just so much to see and do here. 2). but there are still many things to do the 五、用作宾语补足语 1.带 to 的动词不定式作宾语补足语的
8、动词主要有：要 求 允许提议 (ask, allow, , advise)，期 望邀 请鼓励 (expect, , invite, encourage) ， 教导告诉想要 (teach, tell, want)，等待希望愿意(wait for, wish, would like / love)。如： 1) I d invite her to have dinner at my house. 2) We should allow the children to choose their own clothes. 2.动词不定式作补语，在主动语态句里不带to，被动 语态句里带 to 时多数动词是感
9、官动词和使役动词，包 括四“看”：look at, observe, see, watch，三“让”： have, let, make ，二“听” ：hear, listen to ，一“感觉” ： feel，一“注意”：notice 。如： 1)This picture makes me feel excited ！ 2)We saw Liu Yu play baseball last week. 3.help后接动词不定式作补语，to 可带可不带。 1) they can help you to learn English. 5 2)Using email English helps yo
10、u write quickly. 六、用作状语 1.目的状语，置于句首或句末，置于句首时常表示强 调。如： 1) In order to catch the early bus, she got up very early. 2) A group of young people got together to discuss this question. 3) She came to this city to visit her daughter. 2.原因状语，多见于“sb.+be+adj.+to do. ”结构句中。 如： 1) I feel very lucky to have him.
11、 2) He ran out of money to buy old bikes. 3.结果状语，多见于“ too.to ” ， “enough to.”结构 句中。如： 1) Im too tired to do it well. 2)The room is big enough for three people to live in. 七、动词不定式的复合结构 动词不定式的复合结构是“for / of sb. to do sth. ” ，for / of 引出不定式动作的逻辑主语。这种结构在句子中 可以作主语、宾语、表语、定语、状语等。不定式复 6 合结构的介词用for 还是 of，主要决
12、定于前面形容词 的性质。一般说来，of 前面的形容词是careful, clever, foolish, good, kind, nice, wise等，既说明人的特性， 又说明不定式动作的特性。 for 前 面的形容词是 dangerous, difficult, easy, hard, heavy, important, interesting, necessary等，一般说明不定式动作的特 性，前面如果是名词用for。如： 1. It s a good idea for parents to allow children to study in groups during the eve
13、ning. 2. It s wise of him to do it well. 3. Is it interesting for the baby to play with a pet dog? 八、带疑问词的不定式短语 动词不定式前面可以带疑问代词what, which, who 或疑问副词 how, when, where, why 等。 这种结构起名 词的作用，在句子里用作宾语、主语、表语等，或者 单独使用。要注意的是，why 后面的不定式不带to。 如： 1.用作句子的成分。 1) I dont know what to try next. (作宾语 ) 2) Where to go
14、 is not decided yet.( 作主语 ) 2.单独使用时相当于一个特殊疑问句。 1) What to do next?(=What will we / you do next? 7 2) Why go there?(=Why do we / you go there? 九、动词不定式的否定式 不定式的否定式是not / never to do. ， 不带 to 的不定 式的否定式是 not / never do. 如： 1. They decide not to talk to each other. 2. His parents tell him never to play s
15、occer in the street. 随堂练习 I m going to listen to the radio. Please _（not talk ）any more. 2. The students _（do ）their homework from four to five this afternoon. 3. The students _（be）busy now. They _ （have ）an English exam next Monday. 4. Mary must _（look ）after her little sister because she is too yo
16、ung. 5. _ （he）you waiting for a bus now？ 6. This coat is very cheap. I _（take ）it now. 7. Ill tell him about it when he _（come ） back. 8 8. Could you tell me how.I _（can get ） to No 3 Middle school. 9. He _ said that the new teacher _（give ） the students an English lesson now. 10. I _ （milk ）a cow t
17、hree times. 11. Edisons mother _（teach ）him herself. 12. He _ （watch ）TV once a week. 13. Don t speak loudly. The baby _（sleep ）. 14. I won t go out until.I _ （ finish ） my homework. 15. Could you tell me when the train _ （arrive ）. 16. I often hear the sound of children _ （read ）English in the room
18、. 17.He asked me _ （help ） him with his English this evening. 18. Their work is _（clean ）the streets. 19. Did he enjoy _（work ）in China. 9 20. We will stay at home if it _ （rain ） tomorrow. 21. Be quiet！ The boy _ （sing ）an English song. 22. _ you _ your homework yet （start ）？ 23. Who _ （teach ）them
19、 English last term. 24. There _（be） a telephone call for you just now. 25. Please keep everything _（clean ）. 26. Peter wont have a rest until he _（finish ） his work. 27. I watched TV ， so I _（forget ）_（do） my homework. 28. When I _（walk ） along the river ， I met my friend ，Tom. 29. When Mother came
20、， the little girl _ （play ） with a cat. 30. When I was five，I _ _ _ （get ）to know the earth _ （move ）around the sun. 10 31. They _ （see）a boy _ （fall ）into the river while they _（pass ）it yesterday. 32. _（study ）hard at your lessons and（not talk ）in class. 33. You _ （have ）better _ （not eat ）the bad
21、 food. 34. While I _（do ） my homework， my parents _（watch ）TV. 35. He _ （ not finish）_（read ）the book. 36. I _（get ） up very early this morning. I _ （read ）English now. 37. He _ （hurry ）to school every morning. 38. Our teacher _（not stop ）_（work ） until eleven oclock last night. 39. If he _（know ） i
22、t ， he _ （be） very happy. 40. It _ （take ）us half an hour _（read ） English every day. 41. The children _（run ）in the street now. 11 42. There _ （be ）two meetings tomorrow morning. 43. My father _（sleep ）when I _ （get ） up this morning. 44. When I _ （go ）to see Tom ， he _（not write ）anything. 45. Sor
23、ry ， when you _（call ）me， I _ （think ）and _ （not hear ）you. 46. Mr. Green _ （leave ） his notebook at home yesterday. 47. I _（want ） to buy a new coat next Sunday. 48. His father _ （read ）newspaper when I got there. 49. It _ （be）five years since he _（buy ） the motorbike. 50. We found it was very difficult _（get ）a car.