中考英语语法专题详解十专题十非谓语动词一、动词不定式1、构成:动词不定式基本形式为:to+动词原形。
有些动词不定式不带to。
否定形式为:not (to)+动词原形。
2、功能及用法:(1)、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。
如:For him, to talk with his mother is necessary.=It is necessary for him to talk with his mother.(2)、用作表语动词不定式作表语,常说明主语的内容、性质、特征。
常可转换成主语。
如:The best way to improve your English is to join an English club.=To join an English club is the best way to improve your English.(3)、用作宾语★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),宁可拒绝假装知道(prefer, refuse, pretend, know),希望想要愿意(wish, want/need, would like / love)等。
如:We decided to talk to some students.He prefers to eat white bread and rice.★动词decide, know, learn, show, teach, tell...后可用“疑问词+to的不定式短语”作宾语,但why后面的不定式不带to。
如:Could you please tell me where to park my car?★动词feel, find, make, think等后面,可以用it作形式宾语代替真正的宾语—动词不定式,句子结构是sb. feel / find / make / ...+ it+adj. / n.+to do...。
如:I find it difficult to remember everything.★既可接动词不定式又可接v-ing形式作宾语,意思差别不太大的动词有begin, start, like, love等。
如:Then I started to watch English-language TV.I like to eat vegetables.★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ving形式作宾语,表动作已经发生。
stop to do 停下来做另外一件事;stop doing停止做、不做当前这件事。
try to do尽力做,try doing 试试看;go on to do接着做另外的事,go on doing继续做原来的事。
如:When I left home, I had forgotten to bring it with me.I stopped using them last year.(4)、用作定语★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时,用动词不定式的主动式。
如:I have so much homework to do today.It’s a good place to visit.★作定语的不定式如果是不及物动词,且与所修饰的词之间有动宾关系,要在不定式后加适当的介词。
如:I need a room to live in.(5)、用作补语★在主、被动语态句里用带to的动词不定式作补语的动词主要有:要求允许提议(ask, allow, advise),期望邀请鼓励(expect, suppose, invite, encourage),教导告诉想要(teach, tell, want),等待希望愿意(wait for, wish, would like / love)。
如:She asked me not to speak Chinese in English class.★下列动词,多数动词是感官动词和使役动词,当动词不定式作补语时,在主动语态句里不带to,被动语态句里要将省略的to补上。
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:This picture makes me feel tense! I was made to say sorry to him.★help后接动词不定式作补语,to可带可不带。
如:Using email English helps you write quickly.★be said, be sure, happen, seem等后面可以接带to的动词不定式作主语的补语。
如:He doesn’t seem to have many friends.Be sure not to miss them if they come to a city near you.(6)、用作状语, 其逻辑主语要和句子的主语一致。
★目的状语,置于句首或句末,置于句首时常表示强调。
如:A group of young people came here to(in order to) discuss this question.★原因状语,多见于“sb.+be+adj.+to do...”结构句中。
如:I’m sorry to trouble you. I’m glad to see you.★结果状语,多见于“too...to”,“enough to...”结构句中。
如:Then I’m too tired to do well. What should I do?The room needs to be big enough for three people to live in.★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。
如:To be honest, I only eat food that tastes good.To begin with, she spoke too quickly, and I couldn’t understand every word.(7)、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。
不定式复合结构作主语时,需注意:It’s + 形容词+ for / of + sb + to do sth. 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,不说明人的特性。
如:It’s dangerous for children to swim in the river.当上面的形容词指的是sb的性质时,用介词of。
这些形容词往往修饰人:careful, clever, foolish, good, kind, nice, wise,bad, polite, careless如:It’s very nice of you to say so.(8)、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。
如:I don’t know what to do next.Where to go is not decided yet.单独使用时相当于一个特殊疑问句,在复合句中则可变为一个从句。
What to do next? =What will we / you do next?Can you tell me how to do that?=Can you tell me how I should do that?(9)、动词不定式的否定式不定式的否定式是not to do...,不带to的不定式的否定式是not do...如:Sometimes they decide not to talk to each other.(10)常见的与不定式连用的词组和句型。
Why not do…?=Why don’t you do …? had better (not) do …would rather do …prefer to do rather than doCould/Would/Will you please…? It takes sb +时间/金钱+ to do sth.It’s time to do…It’s one’s turn to…如:Why not take a holiday?It takes me an hour to walk there.二、动名词1、构成:动词原形+ing2、功能及用法:动名词除具有动词的性质外,还具有名词的性质。
动名词在句中可用作主语、表语、宾语、定语、宾语补足语等,但不能用作谓语。
(1).用作主语, 谓语动词用单数。
如:Eating too much is bad for your health.注意:动名词作主语经常采用it作形式主语的句型。
It’s no use crying. 哭没有什么用处。
(2).用作表语,可转换成主语。
如:Her favorite sport is skating. =Skating is her favorite sport.注意:不定式和动名词均可用作主语和表语,区别是:动名词多指笼统的、抽象的概念,而不定式则多指具体的、一次性的动作。
(3).用作宾语,放在动词或介词之后。
如:She likes singing and dancing.Thank you for helping us.(4).用作定语,位于所修饰词之前,表示所修饰的词的用途、所属关系等。
如:This is our reading room.Betty won the first prize in the singing competition.★英语中,某些动词(或形容词)只能与ing形式即动名词连用。