動詞不定式講解

1、精選優(yōu)質(zhì)文檔-傾情為你奉上一 動 詞 不 定 式 ：to + 動詞原形1.基本用法：可在句中作主、賓、表、定、狀、補(bǔ)。1）作主語To get up early is a good habit.It's so nice to hear your voice.(it 為形式主語)It is important for us to learn English well.Its silly of you to do such a thing.How to improve our English is still a problem.2) 作賓語We all hope to see you.Th

2、ey found it hard to learn Chinese. （it 為形式賓語）I do not know what to do next. （疑問詞+ 不定式）He asked me how to improve English.（疑問詞 +不定式）3）作表語 一般情況My work is to clean the room every day. His dream is to be a doctor.The question is how to put it into practice. 問題是怎樣把它付諸實施。He seemed to have known the news.

3、如果主語是不定式，則表語也用不定式。例如：To see is to believe.Seeing is believing. 作表語的不定式有時可省略符號to：這時主語部分必須含有動詞do,而作表語的不定式則解釋do 的精確意思。All I did was (to) give him a little help.What we want to do now is (to) have a rest.4)作定語 不定式作定語時，被修飾的名詞常為它的邏輯賓語。不定式與該名詞存在邏輯上的動賓關(guān)系。I have some clothes to wash.（后置定語）He has something im

4、portant to tell you.如果不定式是不及物動詞，后面應(yīng)有必要的介詞。Give me a pen to write with.I need a warm room to live in. 邏輯上的主謂關(guān)系。He was the first teacher to come.I need a box to hold my books.Is there anyone to answer my question?He was the last student to have left the classroom .( 不定式完成式) 邏輯上的同位關(guān)系。Everyone has the r

5、ight to speak at the meeting = Everyone has the right that he may/ can speak at the meeting.Do keep your promise to write to me.= Do keep your promise that you will write to me.5)作狀語 作目的狀語He will go to the station to meet his friend.I often read China Daily in order to (或so as to ) improve my Englis

6、h.（in order to可放在句首； so as to 只能放在句中）。I come here only to say good-bye to you. 作結(jié)果狀語I hurried to his house only to find he was out.He is (not) old enough to join the army.Its too late to play basketball.He was so angry as to be unable to speak. 作原因狀語I was surprised to see him here.They were pleased

7、to hear the good news.I am glad to meet you . 在形容詞后作狀語This question is easy to answer.6）作補(bǔ)語He wants his son to become a lawyer.She encouraged me to try again.They persuaded him to give up smoking.They believe him to be writing a new book .他們認(rèn)為他正在寫一本新書。He wanted the letter to be typed at once .The le

8、tter was wanted to be typed at once.(主補(bǔ))注：有些動詞后跟不帶to 的不定式作賓語補(bǔ)足語。常見的有： 感官動詞feel, hear ,see, watch, notice , observe 使役動詞let, make, have help ：help sb. do 或help sb. to do 兩種說法均可。I often hear him sing this song.The boss made the workers work 12 hours a day.當(dāng)此類句子改為被動語態(tài)時，要補(bǔ)上to.He is often heard to sing t

9、his song.The workers were made to work 12 hours a day. 在 think, find, consider, discover等動詞后常用to be +adj.結(jié)構(gòu)作賓補(bǔ)，有時to be 可省略。We all think/ consider/ find/ discover him (to be) kind and honest. 我們都認(rèn)為/發(fā)現(xiàn)他既善良又誠實。2.不定式的時態(tài)/方式1) 一般式：有時與謂語動詞表示的動作同時發(fā)生，有時發(fā)生在謂語動詞的動作之后。（ to do ）He seems to know this.I hope

10、to see you again. = I hope that I'll see you again.我希望再見到你。2) 進(jìn)行式： 表示動作正在進(jìn)行，與謂語動詞表示的動作同時發(fā)生。(to be doing )He seems to be eating something.3) 完成式：表示的動作發(fā)生在謂語動詞表示的動作之前。(to have done)I'm sorry to have given you so much trouble.He seems to have caught a cold.4) 完成進(jìn)行式： (to have been doing)She is kn

11、own to have been working on the problem for many years.He pretended to have been studying.3. 動詞不定式的否定式 ：not to doTell him not to shut the window.She pretended not to see me when I passed by. 例1）Tell him _ the window.A. to shut not B. not to shut C. to not shut D. not shut答案：B。 tell sb. to do sth 的否定

12、形式為tell sb. not to do sth.例2) She pretended _ me when I passed by.A.not to see B. not seeing C. to not see D.having not seen答案：A。 pretend 后應(yīng)接不定式。其否定形式為pretend not to do sth.。例3）Mrs. Smith warned her daughter _ after drinking.A. never to drive B. to never driver C. never driving D. never drive答案：A。wa

13、rn sb. to do sth. 的否定形式為warn sb.not to do sth. 此處用的是否定詞never.例4) The boy wanted to ride his bicycle in the street，but his mother told him _.A. not to B. not to do C. not do it D. do not to 答案：A。not to 為not to do it 的省略形式。例5) The patient was warned _ oily food after the operation.A. to eat no B. eati

14、ng not C. not to eat D. not eating答案：C。此處為warn sb. to do 的被動否定形式，即be warned not to do。4.動詞不定式的省略1）不定式在使役動詞 let, have, make和感官動詞 see, watch, notice , observe, hear, smell, feel, find 等后作賓補(bǔ)時，省略to。help 可帶to，也可不帶to help sb (to) do sth。2) Why not 后面接不帶to 的不定式。常用來表建議。Why not have a break?3）but和except：but/

15、except前的部分出現(xiàn)實義動詞do時，其后面出現(xiàn)的動詞不定式可以不帶to。He wants to believe anything but to take the medicine. 比較：but前有實義動詞do時，but后的不定式需要省去to. 如：Last night I did nothing but (to )watch TV. He does everything except (to) work. 4) 由and, or或than連接的兩個不定式，第二個不定式的to 可以省去。例如：He wants to move to France and marry the girl.5）通

16、常在discover, imagine, suppose, think, understand等詞后，可以省去to be：He is supposed (to be) an honest man. 例1) - I usually go there by train.- Why not _ by boat for a change?A. to try going B.trying to go C.to try and go D.try going答案：D. why not 后面接不帶to 的不定式，因此選D。例2）Paul doesn't have to be made _. He al

17、ways works hard.A. learn B. to learn C. learned D. learning 答案：B. make后接不帶to 的動詞不定式作賓補(bǔ)，當(dāng)句子是被動語態(tài)時，to要補(bǔ)上。5不定式特殊句型 so as to ：表示目的；其否定式是so as not to do。I often read China Daily so as to improve my English.Tom kept quiet about the accident so as not to lose his job. 湯姆對事故保持沉默是為了不丟掉他的工作。Go in quietly so a

18、s not to wake the baby. 輕點進(jìn)去，別驚醒了嬰兒。注：同樣表示目的，in order to 可放在句首，但so as to 不可放在句首。6不定式特殊句型 too to 1）tooto 太以至不能He is too excited to speak. I'm afraid the box is too heavy for you to carry it。2) 如too前有否定詞，則表達(dá)一種委婉含義，意為"不太"。It's never too late to mend. 改過不嫌晚。3)當(dāng)too 前面有only, all, but時，意思

19、是“非常”，相當(dāng)于very。I'm only too pleased to be able to help you. 我非常高興能幫助你。He was but too eager to go home. 他非常想回家。7. 常見后接動名詞與不定式語義不同的有10 組：(1) stop to do stop doing(2) forget to do forget doing(3) remember to do remember doing(4) regret to do （當(dāng)時或現(xiàn)在遺憾地做什么）regret doing（做了某事而感到遺憾/后悔）(5) cease to do cea

20、se doing (同stop)(6) try to do try doing(7) go on to do go on doing(8) be afraid to do（因害怕而不敢做） be afraid doing（害怕、擔(dān)心某事可能發(fā)生）(9) be interested to do（對做某事感興趣，想了解某事）be interested (in)doing（對某種想法感興趣，doing 通常為想法等）(10) mean to do（打算，意欲）mean doing（意味著）例1.We are not interested _ to stories, but now wed be in

21、terested _ your story.A. in listening, in hearing                        B. to listen, to hearC. in listening, to hear           &

22、#160;                 D. to listen, in hearing解析：此題容易誤選A，因為 be interested in 是大家很熟悉的結(jié)構(gòu)，in 是介詞，其后接動詞自然應(yīng)用動名詞。但是，從句意來看，此題的最佳答案應(yīng)是C。為此請注意以下區(qū)別：be interested in doing sth = 對做某事感興趣（指一般性的動作）be interested to do sth = 很有興趣做某事，很想做某事（指尚未發(fā)生的動作）如：He is interested in listening to stories. 他對聽故事很感興趣。Wed be interested to hear your story. 我們很想聽聽你的故事。請看一個類似的例子：be keen on doing sth = 熱衷于做某