動詞不定式講解 (2)

1、動詞不定式是由“不定式符號to+動詞原形”構(gòu)成的一種非謂語動詞結(jié)構(gòu)。有些動詞不定式不帶to，動詞不定式可以作句子的主語、表語、賓語、定語、補語、狀語或單獨使用。不定式保留動詞的某些特性，可以有自己的賓語、狀語等。動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。現(xiàn)對九年級動詞不定式的用法一次簡要梳理。一、用作主語直接把動詞不定式置于句首的情況不多，多數(shù)情況用it作形式主語，把真正的主語動詞不定式置于句末，特別是不定式短語較長時。動詞不定式作主語，謂語動詞用第三人稱單數(shù)形式。帶疑問詞的不定式短語作主語常置于句首，復(fù)合不定式結(jié)構(gòu)作主語常置于句末。1.As young adults, i

2、t is our duty to try our best to deal with each challenge. 2.The head teacher said it was necessary to talk with his mother.3.How to make requests politely is important.二、用作表語動詞不定式作表語，常說明主語的內(nèi)容、性質(zhì)、特征。如：1.The best way to improve your English is to join an English club. 2.The first thing is to greet th

3、e teacher. 三、用作賓語1.可以接帶to的動詞不定式作賓語的動詞主要有：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 Mexic

4、o.2.動詞decide, 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詞不定式，句子結(jié)構(gòu)是.feel / find / make / . it+adj. / n.+to

5、do.。如：I find it difficult to remember everything. 4.既可接動詞不定式又可接ving形式作賓語，意思差別不太大的動詞有begin, start, like, love等。一般說來，動詞不定式表一次、數(shù)次的具體動作、將來動作或動作的全過程，ving形式表習(xí)慣性的連續(xù)動作。但是這種區(qū)別并不很嚴(yán)格，特別是美國英語，即使習(xí)慣性的動作也可以用動詞不定式。如：1)Then I started to watch English-language TV.2)Im beginning to understand my Chinese roots, and who

6、 I am.begin用了進(jìn)行時態(tài)，后面只接不定式作賓語，表示事情剛開始，還要繼續(xù)下去。3)I like to eat vegetables. 感知動詞like, love, know等一般不用進(jìn)行時態(tài)。5.后接動詞不定式或ving形式作賓語，意思差別較大的動詞有forget, remember等。后接不定式作賓語，表動作尚未發(fā)生；后接ving形式作賓語，表動作已經(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

7、doing繼續(xù)做原來的事。如：1)When I left home, I had forgotten to bring it with me.(p.107)2)I stopped using them last year. (p.121)四、用作定語1.句子的主語或賓語是動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賓關(guān)系時，用動詞不定式的主動式。如：1)I have so many chores to do today.(p.112)2)I cant think of any good advice to give her. (p.31)3)Basketball has a

8、lso become a more popular sport for people to watch.(p.75)2.動詞不定式所修飾的名詞是place, time, way等時，不定式與這些名詞呈現(xiàn)出動狀關(guān)系或同位關(guān)系。如：1)He needs time to do homework.(p.19)2)Is that a good place to hang out？(p.88)3)You want to know the best way to get around the city.(p.127)3.在“there be.”句型里，句子的主語是動詞不定式動作的對象，常用主動式。如：1)T

9、heres just so much to see and do here.(p.49)2). but there are still many things to do there.(p.54)五、用作補語動詞不定式作補語時，在主動語態(tài)句里補賓語，在被動語態(tài)句里補主語，句子的賓語或主語是不定式動作的邏輯執(zhí)行者。如果不定式是to be done，句子的賓語或主語就是邏輯承受者。1.在主、被動語態(tài)句里用帶to的動詞不定式作補語的動詞主要有：要求允許提議(ask, allow, permit, advise)，期望邀請鼓勵(expect, suppose, invite, encourage)，教

10、導(dǎo)告訴想要(teach, tell, want)，等待希望愿意(wait for, wish, would like / love)。如：1)Id invite her to have dinner at my house.(p.29)2)Teenagers should be allowed to choose their own clothes. (p.18)3)Email English is supposed to be used on mobile phones.(p.101)2.動詞不定式作補語，在主動語態(tài)句里不帶to，被動語態(tài)句里帶to時多數(shù)動詞是感官動詞和使役動詞，包括四“看”

11、：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 makes me feel tense！(p.106)2)Of course we want to see Liu Yu achieve his dreams.(p.24)3.help后接動詞不定式作補語，to可帶可不帶。一般說來，帶to表間接幫助，不帶to表直接幫助。在被動語態(tài)句里，或者用不定式的否定式作補語時要帶to。如：1). they can help you t

12、o compare two different products so that you can buy the one you really need.(p.106)2)Using email English helps you write quickly. (p.100)4.be said, be sure, happen, seem等后面可以接帶to的動詞不定式作主語的補語。如：1)He doesnt seem to have many friends.(p.19)2)Be sure not to miss them if they come to a city near you.(p.

13、114)六、用作狀語1.目的狀語，置于句首或句末，置于句首時常表示強調(diào)。如：1)In order not to offend people, learning about language etiquette is just as important as learning grammar or vocabulary.(p.93)2)A group of young people got together to(in order to / so as to) discuss this question. (p.50)to do / in order to do / so as to do用作目

14、的狀語，置句末時都可以用，置句首時只用to do / in order to do。so as to do一般不置于句首，可以引導(dǎo)結(jié)果狀語從句，in order to do不引導(dǎo)結(jié)果狀語從句。2.原因狀語，多見于“sb.+be+adj.+to do.”結(jié)構(gòu)句中。如：1)My dogs name is “Lucky”a good name for him because I feel very lucky to have him.(p.66)2)On Monday he told a radio interviewer that he had run out of money to buy ol

15、d bikes. (p.64)3.結(jié)果狀語，多見于“too.to”，“enough to.”結(jié)構(gòu)句中。如：1)Then Im too tired to do well. What should I do?(p.28)2)The room needs to be big enough for three people to live in.(p.56)4.有些動詞不定式作狀語，常說明前面形容詞的性質(zhì)和特性。動詞不定式與句子的主語有邏輯的動賓關(guān)系。動詞不定式前面的形容詞一般是：cheap, dangerous, difficult, easy, fun, hard, interesting, ne

16、cessary。不定式常用主動式表被動意義。. the mistakes you made are necessary for you to learn and understand.(p.116)這類句子中的動詞不定式可改為主語。5.獨立動詞不定式多用作插入語，表示說話人的心理狀態(tài)或?qū)κ虑榈目捶āＨ纾?)Id like to stay healthy, but to be honest, I only eat food that tastes good.2)To begin with, she spoke too quickly, and I couldnt understand every

17、 word. 七、動詞不定式的復(fù)合結(jié)構(gòu)動詞不定式的復(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，又說明不定式動作的特性。for前面的形容詞是dangerous, difficult, easy, hard, heavy, important, interesting, nece

18、ssary等，一般說明不定式動作的特性，不說明人的特性。前面如果是名詞用for。如：1.Its also probably a good idea for parents to allow teenagers to study in groups during the evening.2.Zoos are terrible places for animals to live.八、帶疑問詞的不定式短語動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，在句子里用作賓語、主語、表語等，或者單獨使用。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. (p.49)(作賓語)2)Where to go is not decided yet.(作主語)2.單獨使用時相當(dāng)于一個特殊疑問句。1