1、动词不定式动词不定式是一种活跃的非谓语动词。它在句中起的是名词、形容词或副词的作用，可在句子中作主语、宾语、定语、状语和宾语补足语。动词不定式的基本形式是“ 不定式符号 to+动词原形”，有时可以不带 to。动词不定式没有人称和数的变化。在句中不能单独作谓语，但仍保留动词的特性，可以有自己的宾语、状语等。动词不定式同它的宾语和状语一起构成不定式短语。例如：to sell flowers in the street 在街上卖花 to speak in the classroom 在教室里讲话巧记动词不定式的用法：不定式有标记，to 与动原连一起。没有人称数变化，动词特点它具备。主宾定状表补语，唯
2、独作谓不可以。not 加上不定式，否定结构要牢记。疑问词与不定式，构成短语有意义。仔细推敲多思考，准确判断有依据。一、带 to 的不定式结构1.我们学过的能直接跟带 to 的不定式结构的动词主要有：want, ask, tell, hope, learn, try, decide, forget, remember, like, love, stop, go, come 等。2.动词不定式的否定形式是在不定式前直接加 not, 即 not to do sth. 例如:Jim told me not to wake up Kate.吉姆告诉我别叫醒凯特。二、不带 to 的不定式结构以下几种情况使
3、用不带 to 的动词不定式:1.在固定词组 would rather 和 had better 之后。注意：had better 的否定形式是 had better not do sth.。例如:You had better go home now.你最好现在回家。Its cold outside. Youd better not go out.外面很冷,你最好不要出去。2. 使役动词 let, make, have 等使役动词后，要跟不带 to 的动词不定式作宾语补足语。例如: Let him go!I made them give me the money back.我迫使他们把钱还给我。
4、3感官动词 see, watch, look at, hear, listen to, smell, feel, find，notice 等后作宾语补足语，省 to。 例如：I saw him dance.4. 在引导疑问句的 why/why not 之后。“Why not+ 不带 to 的不定式“是 Why dont you do的省略，可以用来提出建议或劝告。例如:Why not go with us？什么不和我们一起去呢?Why not take a holiday? =Why dont you take a holiday? 为什么不休个假呢？5.help 可带 to，也可不带 to,
5、 help sb (to) do sth6.由 and, or 和 than 连接的两个不定式，第二个 to 可以省去举例：He wants to do nothing but go out.他什么都不想做除了出去。He wants to move to France and marry the girl.他想搬去法国并娶那个女孩儿。典型例题- 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
6、案：D. why not 后面接不带 to 的不定式，因此选 D。三、动词不定式作主语直接把动词不定式置于句首的情况不多，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。带疑问词的不定式短语作主语常置于句首。To teach English is my favorite.教英语是我的爱好。 Its my pleasure to help you.很乐意帮助你。 How to learn English well is important.如何学好英语是重要的。动词不定式作主语时可以放在后面，而用 it 作形式主
7、语放在原主语的位置上。 1）Its+ adj.+ for sb.to do sth.常用于表示事物的特征特点，表示客观形式的形容词，如 easy, hard, difficult, interesting, impossible, important, possible, impossible, comfortable, necessary, better，the first, the next, the last, the best, too much, too little, not enough 等。Its so nice to hear your voice. 听到你的声音真高兴。It
8、s very hard for him to study two languages. 对他来说学两门外语是很难的。2）Its + adj.+ of sb. to do sth.的句型一般用表示人物的性格，品德，表示主观感情或态度的形容词，如 good, kind, nice, clever, foolish, right, brave, silly（笨的）, selfish(自私的), selfless(无私的)等。Its very nice of you to help me. 你来帮助我，你真是太好了。拓展：for 与 of 的辨别方法：用介词后面的代词作主语，用介词前边的形容词作表语，
9、造个句子。如果道理上通顺用 of，不通则用 for。如：You are nice. (通顺，所以应用 of)。He is hard. (人是困难的，不通，因此应用 for。)注意：1) 其他系动词如，look，appear 等也可用于此句型2) 不定式作为句子成分时，动词用单数形式。3) 当不定式作主语的句子中又有一个不定式作表语时，不能用 It is to的句型(对)To see is to believe. 百闻不如一见。(错)It is to believe to see.四、动词不定式作定语不定式作定语，要放在它所修饰的名词或代词的后面。例如:I have nothing to say
10、 on this question.对这个问题我无可奉告。通常 chance, place, time, way 等名词后接不定式作定语。另外在 the first, the second, the last, the only 等词后，也常用不定式作定语。例如：He needs time to do homework.他需要时间写作业。 She wants to know the best way to get good grades.她想知道得好成绩的最好方法。五、动词不定式作宾语1. 用作宾语的动词不定式，常用在动词 ask, choose, agree，expect, hope, de
11、cide, learn，prefer, know ，wish, want, would like, afford(付得起)， agree， ask， decide， desire（渴望），fail， plan， prepare（准备）， promise， refuse，(help)等及物动词之后，构成动宾短语。例如：We decided to take the train to Beijing. 我们决定坐火车去北京。He prefers to eat rice. 他更喜欢吃米饭。2.动词 feel, find, make, think, believe 等，在语法上不能接受不定式作宾语，只有
12、用 it 作形式宾语，从而把动词不定式后置。句子结构是：主语feel / find / make / . +it+adj. / n.+to do.。例如：I find it useful to learn English well.我发现学好英语很有用。We thought it wrong not to tell her.我们认为不告诉她是错误的。拓展：除动词不定式做宾语外，动名词和动词原形也能做宾语。3.既可接动词不定式又可接 v-ing 形式作宾语，意思差别不大的动词有 begin, start, like, love 等。例如：Then I started to watch Engli
13、sh-language TV.4.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。1、 stop to do 停止，中断做某事后去做另一件事 stop doing 停止做某事2 、 forget to do 忘记要去做某事 forget doing 忘记做过某事 3、 remember to do 记得去做某事 remember doing 记得做过某事 4、 try to do 努力做某事 try doing 试着做某事 5、 go on to do 做了一件
14、事后，接着做另一件事 go on doing 继续做原来做的事 6、 mean to do 打算去做某事 mean doing 意味着例如：When I left home, I had forgotten to bring it with me.I stopped using them last year. 5.后只接 v-ing 作宾语的一些常用特殊动词：give up, enjoy, practice, finish, mind 等。例如： Would you mind opening the window? 6. 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
15、, 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。后接“疑问词+ to do ”作宾语的一些常用特殊动词:decide, know, forget, learn, remember, show, understand, see, wonder, hear, find out, tell例如：I dont know what to do next. （作宾语） I cant decide which to buy.我拿不定主意买哪一种。注意 :疑问词带不定式在句中
16、作成分时，谓语动词用单数。The question is how to remember this word. 问题是怎样把这个单词记住。六、动词不定式作宾语补足语1. 动词不定式作下列这些动词的宾语补足语时，动词不定式符号 to 不可以省略。动词主要有：要求允许提议警告（ask, advise ），期望邀请鼓励（ expect, invite），教导告诉想要（teach, tell, want），希望愿意（ wish, would like / love）。例如：I like you to keep everything tidy. 我喜欢你年使每件东西都保持整洁。I want you to
17、 speak to Tom. 我想让你和汤姆谈话。2. 动词不定式作下列单词的补语时，动词不定式符号 to 要省略，包括三“视”：look at, see, watch; 二“听 ”：hear, listen to; 一“感觉”：feel; 半“帮助”：help; 三“让”：have, let, make; 一“注意”：notice 。例如：This movie makes me feel happy.这个电影让我感觉快乐。3. 作动词 help 的宾语补足语时,动词不定式符号 to 可以带，也可以不带。例如： She helps me (to) clean the classroom qui
18、ckly. 七、动词不定式作状语动词不定式及其短语具有副词的特性，可在句中用作状语。1.目的状语，置于句首或句末，置于句首时常表示强调。为加强语气，常与 in order 或 so as 组成短语。例如：He stopped to have a rest.他停下来休息。In order to help him, we would do everything we can.为了帮助他，我们愿意做我们能做的一切。2.原因状语，跟在作表语的形容词或过去分词的后面。多见于“sb.+ be+ adj.+ to do.”结构句中。例如：I was very sad to hear the news. 听到
19、这个消息我很难过。3.结果状语，多见于“too.to 太以至于不能”，“adj. +enough to do sth.足够怎么样去做某事”结构句中。例如：He is too young to understand that.他太年轻了，不能理解这件事。 He is old enough to go to school .他足够大去上学了。4.独立动词不定式多用作插入语，表示说话人的心理状态或对事情的看法。例如：To be honest, I dont know how to swim.说实话，我不知道怎么游泳To begin with, I want to show my love to ev
20、eryone.首先，我想向每个人表达我的爱。 八、 不定式作表语不定式可放在系动词后面，形成表语。例如：例如：My work is to clean the room every day.我的工作室每天打扫房间。His dream is to be a doctor.他的梦想是成为一名医生。拓展动词作下列单词的补语时，可用动词原形（do）,也可用动名词（doing ），包括：感官动词 （see, watch, look at, hear, listen to, feel）+ do 表示动作的完整性，真实性，经常发生；+doing 表示动作的连续性，进行性。例如：I saw him work i
21、n the garden yesterday.昨天我看见他在花园里干活了。(强调“我看见了 “这个事实或经常性)I saw him working in the garden yesterday.昨天我见他正在花园里干活。（强调“我见他正干活“ 这个动作）典型例题1）They knew her very well. They had seen her _ up from childhood.A. grow B. grew C. was growing D. to grow答案：A。因题意为，他们看着她长大，因此强调的是成长的过程，而非正在长的动作，因此用 see sb. do sth. 的句型
22、。巩固练习1、He read the instruction to find out how _ the computer. A. use B. to use C. using D. uses2、There are some dangerous fishes in this river, and I warned Jack _here.A. not to swim B .to not swim C. swim not to D. to swim not3、The article said that he hoped _ drawing the picture soon.A. his son t
23、o finish B. to finish C. finish D. his son will finish4、Listen! Can you hear a baby _ ? A. cry B. to cry C. crying D. cries5、Dont always make Mike _ this or that. He is already a big boy.A. do B. to do C. does D. did6、Dont forget _ the letter. A. to send B. send C. sending7、Tell him _ the light.A. t
24、o turn B. not to turn on C. to not turn D. not to turn8、Thank you very much _ the present. A. to give me B. for giving me C. giving me 9、I have no paper. Could you give me a piece of paper _ ? A. to write in B. write in C. to write on 10、It took us more than two hours _ the dinner.A. prepare B. prep
25、aring C. to prepare D. to be prepared11、We felt the earth _.A. move B. moving C. to move D. be moved12、Nobody knows _next.A. what to do B. to do what C. which to do D. how to do13、It is very important _ us _these words.A. to, to remember B. for, to remember C. for, remember D. for, remembering14、On
26、my way home, I stopped _ some food. A. buy B. to buy C. buying15、_ English well, one must have a lot practice.A. For speaking B. Speaking C. To speak D. Speak16、Im going to the library _ the books.A. return B. borrow C. to return D. to lend17、The funny story _ me laugh.A. make B. making C. to make D. made18、After the final exam, I think all the students want _.A. stop to have a rest B. to stop having a restC. to stop to have a rest D. stopping to have a rest
