八年級(jí)動(dòng)詞不定式

1、八年級(jí)英語動(dòng)詞不定式用法梳理動(dòng)詞不定式是由“不定式符號(hào)to+動(dòng)詞原形”構(gòu)成的一種非謂語動(dòng)詞結(jié)構(gòu)。有些動(dòng)詞不定式不帶to，動(dòng)詞不定式可以作句子的主語、表語、賓語、定語、補(bǔ)語、狀語或單獨(dú)使用。不定式保留動(dòng)詞的某些特性，可以有自己的賓語、狀語等。動(dòng)詞不定式和它后面的賓語、狀語等一起構(gòu)成短語，叫作不定式短語。一、用作主語多數(shù)情況用it作形式主語，把真正的主語動(dòng)詞不定式置于句末，特別是不定式短語較長(zhǎng)時(shí)。動(dòng)詞不定式作主語，謂語動(dòng)詞用第三人稱單數(shù)形式。疑問詞+不定式短語作主語可置于句首，復(fù)合不定式結(jié)構(gòu)作主語常置于句末。如：1. It is our duty to try our best to deal w

2、ith 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.(眼見為實(shí)；百聞不如一見)二、用作表語動(dòng)詞不定式作表語，常說明主語的內(nèi)容、性質(zhì)、特征。如：1.The best way is to join an English club. 2.The first thing is to listen to the teacher carefully. 三、用作賓

3、語1.可以接帶to的動(dòng)詞不定式作賓語的動(dòng)詞主要有：要求選擇同意(ask, choose, agree)，期望決定學(xué)習(xí)(expect, hope, decide, learn)，寧可假裝知道(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 bread and rice.3)Id love to visit Mexico.2.動(dòng)詞decide,

4、know, learn, show, teach, tell.，介詞結(jié)構(gòu)on.可用疑問詞帶to的不定式短語作賓語，但why后面的不定式不帶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.動(dòng)詞feel, find, make, think等后面，可以用it作形式賓語代替真正的賓語動(dòng)詞不定式，句子結(jié)構(gòu)是.feel / find / make / . it+adj. / n.+to do.。如：4. 感知?jiǎng)釉~l

5、ike, love, know等一般不用進(jìn)行時(shí)態(tài)。5.后接動(dòng)詞不定式或v-ing形式作賓語，意思差別較大的動(dòng)詞有forget, remember等。后接不定式作賓語，表動(dòng)作尚未發(fā)生；后接v-ing形式作賓語，表動(dòng)作已經(jīng)發(fā)生。stop to do停下來做另外一件事，to do是目的狀語；stop doing停止做、不做當(dāng)前這件事，doing是賓語。try to do盡力做，try doing試試看；go on to do接著做另外的事，go on doing繼續(xù)做原來的事。如：1)When I left home, I forgot to bring it with me.2)I stopped

6、 using them last year. 四、用作定語1.句子的主語或賓語是動(dòng)詞不定式的邏輯主語，不定式與其所修飾的名詞、代詞等存在邏輯的動(dòng)賓關(guān)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.動(dòng)詞不定式所修飾的名詞是place, time, way等時(shí)，不定式與這些名詞呈現(xiàn)出動(dòng)狀關(guān)系或同位關(guān)系。如：1)He needs time to do homework.2) He wants to know

7、the best way to travel around the city.3.在“there be.”句型里，句子的主語是動(dòng)詞不定式動(dòng)作的對(duì)象：1) Theres just so much to see and do here.2). but there are still many things to do the五、用作賓語補(bǔ)足語1.帶to的動(dòng)詞不定式作賓語補(bǔ)足語的動(dòng)詞主要有：要求允許提議(ask, allow, , advise)，期望邀請(qǐng)鼓勵(lì)(expect, , invite, encourage)，教導(dǎo)告訴想要(teach, tell, want)，等待希望愿意(wait for

8、, wish, would like / love)。如：1) Id invite her to have dinner at my house.2) We should allow the children to choose their own clothes. 2.動(dòng)詞不定式作補(bǔ)語，在主動(dòng)語態(tài)句里不帶to，被動(dòng)語態(tài)句里帶to時(shí)多數(shù)動(dòng)詞是感官動(dòng)詞和使役動(dòng)詞，包括四“看”：look at, observe, see, watch，三“讓”：have, let, make，二“聽”：hear, listen to，一“感覺”：feel，一“注意”：notice。如：1)This picture

9、 makes me feel excited！2)We saw Liu Yu play baseball last week.3.help后接動(dòng)詞不定式作補(bǔ)語，to可帶可不帶。1) they can help you to learn English.2)Using email English helps you write quickly. 六、用作狀語1.目的狀語，置于句首或句末，置于句首時(shí)常表示強(qiáng)調(diào)。如：1) In order to catch the early bus, she got up very early.2) A group of young people got toge

10、ther to discuss this question. 3) She came to this city to visit her daughter.2.原因狀語，多見于“sb.+be+adj.+to do.”結(jié)構(gòu)句中。如：1) I feel very lucky to have him.2) He ran out of money to buy old bikes. 3.結(jié)果狀語，多見于“too.to”，“enough to.”結(jié)構(gòu)句中。如：1) Im too tired to do it well. 2)The room is big enough for three people

11、to live in.七、動(dòng)詞不定式的復(fù)合結(jié)構(gòu)動(dòng)詞不定式的復(fù)合結(jié)構(gòu)是“for / of sb. to do sth.”，for / of引出不定式動(dòng)作的邏輯主語。這種結(jié)構(gòu)在句子中可以作主語、賓語、表語、定語、狀語等。不定式復(fù)合結(jié)構(gòu)的介詞用for還是of，主要決定于前面形容詞的性質(zhì)。一般說來，of前面的形容詞是careful, clever, foolish, good, kind, nice, wise等，既說明人的特性，又說明不定式動(dòng)作的特性。for前面的形容詞是dangerous, difficult, easy, hard, heavy, important, interesting,

12、necessary等，一般說明不定式動(dòng)作的特性，前面如果是名詞用for。如：1. Its a good idea for parents to allow children to study in groups during the evening. 2. Its wise of him to do it well.3. Is it interesting for the baby to play with a pet dog?八、帶疑問詞的不定式短語動(dòng)詞不定式前面可以帶疑問代詞what, which, who或疑問副詞how, when, where, why等。這種結(jié)構(gòu)起名詞的作用，在句子

13、里用作賓語、主語、表語等，或者單獨(dú)使用。要注意的是，why后面的不定式不帶to。如：1.用作句子的成分。1) I dont know what to try next. (作賓語)2) Where to go is not decided yet.(作主語)2.單獨(dú)使用時(shí)相當(dāng)于一個(gè)特殊疑問句。1) What to do next?(=What will we / you do next?2) Why go there?(=Why do we / you go there?九、動(dòng)詞不定式的否定式不定式的否定式是not / never to do.，不帶to的不定式的否定式是not / never

14、 do.如：1. They decide not to talk to each other.2. His parents tell him never to play soccer in the street.隨堂練習(xí)Im 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 ne

15、xt Monday.4. Mary must _（look）after her little sister because she is too young.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. Could you tell me how.I _（can get）to No 3 Middle school.9. He _ said that the new teacher _（giv

16、e）the students an English lesson now.10. I _（milk）a cow three times.11. Edisons mother _（teach）him herself.12. He _（watch）TV once a week.13. Dont speak loudly. The baby _（sleep）.14. I wont go out until.I _（finish）my homework.15. Could you tell me when the train _（arrive）.16. I often hear the sound o

17、f children _（read）English in the room.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.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. Wh

18、o _（teach）them 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 ，th

19、e little girl _（play）with a cat.30. When I was five，I _ _ _（get）to know the earth _（move）around the sun.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 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.