动词不定式的用法课件.pptx
非谓语动词非谓语动词,又叫非限定动词,非谓语动词是指在句子中不是谓语的动词,主要包括非谓语动词除了不能独立作谓语外,可以承担句子的其他成分。不定式不定式 (to+v)动动名名词词 (v-ing)即即动词动词的非的非谓语谓语形式形式分分词词(现现在分在分词词和和过过去分去分词词)非谓语动词没有人称和数的变化。动词不定式是一种非谓语动词形式,其结构为“to动词原形”,其中to不是介词,而是动词不定式的符号,称为小品词,动词不定式没有人称和数的变化。动词不定式和其后面的名词等构成不定式短语,在句子中可以用作主语、表语、宾语、补足语、定语、状语等。肯定式:to do sth否定式:not to do sth被动式:to be done完成式:to have done目录目录1动词不定式做动词不定式做主语主语2动词不定式动词不定式做做表语表语3动词不定式动词不定式做做宾语宾语4动词不定式动词不定式做做补足语补足语5动词不定式动词不定式做做定语定语6动词不定式动词不定式做做状语状语To be a doctor is hard.做医生很难。To learn English well is not easy.学好英语不容易。To say is to believe.眼见为实。因为动词不定式没有人称和数的变化,所以,动词不定式做主语时,谓语动词用第三人称单数动词不定式(短语)作主语时,为了避免句子的头重脚轻,可以用“it”作形式主语,而把真正的主语动词不定式(短语)放在句子的后部。例如上面的句子可以表示为:It is hard to be a doctor.It is not easy to learn English well.Its important to plant trees in spring.如果动词不定式的动作是谁做的,可以在动词不定式前面加一个由介词for引导的短语,称为不定式的复合结构。例:Its good for us to read English aloud in the morning.对我们来说每天早晨大声读英语是很有益的。It is important for students to use English every day.对学生来说每天使用英语是很重要的。不定式作表语有两种情况:一、主语为不定式,二、主语为抽象名词To say is to believe.眼见为实。My job is to help the patient。我的工作是帮助病人 动词不定式(短语)作表语常用于系词be的后面。例:His work is to drive a car.他的工作是开车。My job is to feed animals.我的工作是饲养动物。Her ambition is to be a doctor.她的理想是当医生。All I want to do now(what I want to do now)is fill my stomach。动词不定式(短语)可以放在一些动词后面用作宾语,能以动词不定式作宾语的动词有:begin,start,want,forget,remember,show,learn,like,hate,love,ask等。例:I want to tell you a story.我想给你讲个故事。They begin to work at eight every morning.他们每天早晨8点开始工作。Dont forget to lock the door.别忘了锁门。Would you like to go and have a picnic with us tomorrow?明天和我们一起去野餐好吗?*如果and连接两个动词不定式,第二个动词不定式一般省“to”例:He wants to go and have a swim with us.他想和我们一起去游泳 若作宾语的动词不定式(短语)带有宾语补足语,往往把不定式短语放在宾补后,用it作形式宾语。句型为:主语+find(feel,think belive,consider,etc)+it+adjn+to do sth。I find it interesting to learn English with you.我觉得和你一起学英语很有趣。He found it hard to catch up with others.他觉得赶上别人很困难。动词不定式还可用作介词宾语,但仅限于介词except和but 常用句型:there is nothing to do but+vdo nothing but+vcan but+v(只有做)have no choice but to do cannot help/choose but+v The teacher asked us to read English for half an hour in the morning.老师让我们早晨读半小时英语。The teacher often tells Jim not to spend too much time playing computer games.老师常告诉Jim不要花太多时间玩电脑游戏。Please let me help you.让我来帮助你。动词不定式作宾语补足语,表示宾语所做的动作,可以用动词不定式作宾语补足语的动词有:tell,ask,want,like,invite,encourage,help等。但在let,make,see,watch,hear,feel,notice,have等感官听觉动词或使役动词后面作宾语补足语的动词不定式一般要省略动词不定式符号“to”,1.不可以省to的不定式作宾语补足语:tell/ask/want/would like/wish/like/invite/encourage/teach sb.to do sth.例:The teacher told us to come earlier tomorrow.I want you to go now.我想让你现在就走。Her parents wish her to be a teacher.她父母亲希望她当老师。2.省“to”的不定式作宾语补足语:Let/make/have sb.do sth.Let the boy go out now.让那个男孩出去。The boy made the baby cry.男孩弄哭了这个小孩。see/watch/hear/notice/feel sb.do sth.I saw the students play basketball on the playground yesterday.昨天我看见学生们在操场打篮球。I often hear the girl sing in the next room.我经常听到女孩在隔壁唱歌。3.可省可不省的:help sb.(to)do sth.I often help my mother(to)do housework.我经常帮妈妈做家务。*动词不定式的否定式是直接在to之前加not.例:(1)Tell them not to play football in the street.告诉他们不要在街道上踢足球。(2)省to的动词不定式的否定式是直接在动词前面加not.例:Let the boy not go.让那个男孩别走。(3)如果将主动语态变为被动语态时,作宾语补足语的动词不定式变为主语补足语,动词不定式则不省“to”,即原来省的再加上,例:The boy made the baby cry.The baby was made to cry by the boy.那个孩子被男孩弄哭了。动词不定式作定语常用来修饰名词或不定代词,放于所修饰的词后,为后置定语。例:Who was the first one to arrive?谁第一个到的?She has no paper to write on?她没有纸写字?The best way to learn English is to use it.学英语最好的方法是使用它。When is the best time to plant vegetables?什么时候是种植蔬菜的最好时间?Do you have something to drink?你这有喝的吗?*动词不定式(短语)作定语修饰名词时,与其所修饰的词具有一种动宾关系,如果不定式中的动词为不及物动词时,其后应加上一个含义上所需要的介词。例:I have no chair to sit on.我没有椅子坐。He has no house to live in.他没有房子住。不定式做状语,可表示动作的目的、结果、原因、条件和方式。动词不定式作目的状语常用在go,come,hurry等不及物动词后,表目的。He went to see his sister yesterday.他昨天去看妹妹了。They got up early to catch the early bus.他们早起去赶早班车。有时可以把不定式(短语)提前,放于句首,表示强调目的。例:To learn English quickly and well,he went to England.为了更快更好地学英语,他去了英国。表目的时,不定式可放在句子的前面也可放在句子的末尾。但在句子前面时,不定式常与句子用逗号隔开;而在句子末尾时一般不用逗号隔开。如:To get there on time,we set out at five in the morning.为了按时到达那儿,我们早晨五点就出发了。He goes there to enjoy the fresh air.他去那儿享受那儿的新鲜空气。比较:to do,in order to do,so as to do都可表示目的,但to do,in order to do的位置既可在句首,又可在句末;而so as to do只能在句末-In order to build a house,he bought some wood and steel yesterday.He bought some wood and steel yesterday in order to build a house.-He bought some wood and steel yesterday so as to build a house.为了建房,昨天他买来了木料和钢材。不定式表示原因时,一般放在句子的末尾,说明主语某种心情、情感(glad,pleased,sad,worried,sorrow,excited)所产生的原因。如:Im very glad to hear that Li Lei has been elected secretary of the Party.听说李蕾被选为了党的书记,我很高兴。不定式表示条件时,一般放在句首。如:To be heated,liquid will change into gas.如果受热,液体就会变成气体。不定式可接在as if/as though之后表示方式时,如:He moved his mouth as if to say something.他的嘴唇动了动,好像要说什么事似的。不定式在下列结构中表示谓语动作的结果,不定式的位置一般在句子末尾。(1)表示终结性的动词find,see,hear,learn,discover的不定式,常表示出乎意料的结果,并且,不定式前常有never,only等副词修饰。如:I hurried to the railway station yesterday,(only)to find that the train had left.昨天我急急忙忙赶到火车站时,发现火车已经开走了。I went to the classroom,to discover it empty.我走到教室,结果发现教室是空的。(2)在“so+adj./adv.+as+to do”中。如:The scenery is so beautiful as to attract many people here every year.景色非常美,每年都要吸引很多人来这里。(3)在“adj./adv.+enough+to do”中。如:He ran fast enough to catch up with Li Lei.他跑得很快,结果赶上了李蕾。(4)在“so+adj./adv.+a(n)+n.+as+to do”中。如:This is so interesting a story as to interest children.这是个很有趣的故事,使孩子们非常感兴趣。(5)在“such+adj./adv.+n.+as+to do”中。如:She is such a good girl to help you make great progress.她是个非常好的姑娘,帮助你取得了很大的进步。(6)在“too+adj./adv.+to do”中。如:They went too slowly to catch the early bus.他们走得太慢了,结果没能赶上早班车。七.不定式和疑问词连用,可以作句子的主语、宾语、表语等。例:The problem is where to get a computer.(表语)No one knows how to do it.没有人知道如何做这件事。(宾)I really dont know which one to choose.(宾)我真的不知道选哪一个。When and where to have the party is not known.(主语)何时何地举行联欢还不知道。*不定式和疑问词连用作宾语时有时可以改为宾语从句。例:I dont know what to do next.我不知下一步该做什么?I dont know what I should do next.1.He asked me _ here earlier.A.come B.to come C.coming D.came 2.Please tell him _ on the wall.A.dont draw B.to not draw C.not to draw D.not draw 3.He wanted _ a cup of tea.A.to have B.having C.have D.had 4.Id like _ a word with you.A.had B.having C.to have D.have 5.I came here _ my uncle.A.saw B.to see C.seeing D.to be seenpracticepracticeBACBCB6.The man refused(拒绝)_ back his words.A.to take B.taking C.took D.takes 7.I can let you _ one ticket.A.to have B.have C.having D.had 8.We often heard him _ in his room.A.to sing B.sings C.sang D.sing 9.He was made _ day and night.A.work B.working C.to work D.worked 10.He stopped _ a look,but saw nothing.A.having B.to have C.have D.hadpracticepracticeABDCB