9大語(yǔ)法難點(diǎn)（3）七、虛擬語(yǔ)氣如果我們所說(shuō)的不是事實(shí)，而只是一種假設(shè)、愿望、建議或是一種實(shí)現(xiàn)不了的空想就用虛擬語(yǔ)氣。注意：條件句分兩種，真實(shí)條件句和虛擬條件句。只有在虛擬（非真實(shí)）條件句中，才用虛擬語(yǔ)氣；而在真實(shí)條件句中,要用陳述語(yǔ)氣。請(qǐng)比較：（1）If it is sunny tomorrow , well go to the zoo. 如果明天天氣好,我們將會(huì)去公園。在這句話中，明天天氣好是完全有可能實(shí)現(xiàn)的，并非虛擬、幻想，因此是真實(shí)條件句，在本句中，適用“主將從現(xiàn)。”（2）If I were you , I would go at once. 如果我是你的話，我立刻就走。在這句話中，條件句“如果我是你”，但事實(shí)上，我不可能成為你，這只是假設(shè)的情況，沒(méi)有實(shí)現(xiàn)的可能。當(dāng)條件實(shí)現(xiàn)的可能性很小，甚至可以說(shuō)沒(méi)有時(shí)，就需要用虛擬語(yǔ)氣來(lái)表示。虛擬語(yǔ)氣表示和現(xiàn)在的事實(shí)相反，從句用一般過(guò)時(shí)，主句用 “should/would/could/ might +動(dòng)詞原形。If I had time, I would go for a walk.If I were invited, I would go to the dinner party.If I won a million dollars in the lottery, I would put it in the bank.If I were you , Id wear a shirt and tie.注意：在虛擬語(yǔ)氣的句子中，be動(dòng)詞只能用were，不能用was。八、動(dòng)詞不定式動(dòng)詞不定式是由“不定式符號(hào)to+動(dòng)詞原形”構(gòu)成的一種非謂語(yǔ)動(dòng)詞結(jié)構(gòu)。有些動(dòng)詞不定式不帶to。動(dòng)詞不定式可以作句子的主語(yǔ)、表語(yǔ)、賓語(yǔ)、定語(yǔ)、補(bǔ)語(yǔ)、狀語(yǔ)或單獨(dú)使用。不定式保留動(dòng)詞的某些特性，可以有自己的賓語(yǔ)、狀語(yǔ)等。動(dòng)詞不定式和它后面的賓語(yǔ)、狀語(yǔ)等一起構(gòu)成短語(yǔ)，叫作不定式短語(yǔ)。1. 用作主語(yǔ)直接把動(dòng)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(yǔ)，把真正的主語(yǔ)動(dòng)詞不定式置于句末，特別是不定式短語(yǔ)較長(zhǎng)時(shí)。動(dòng)詞不定式作主語(yǔ)，謂語(yǔ)動(dòng)詞用第三人稱(chēng)單數(shù)形式。帶疑問(wèn)詞的不定式短語(yǔ)作主語(yǔ)常置于句首。It is our duty to try our best to deal with these problems.盡最大努力處理這些問(wèn)題是我們的責(zé)任。The head teacher said it was necessary to talk with his mother.校長(zhǎng)說(shuō)，和他媽媽談一談很有必要。How to learn English well is important.如何學(xué)好英語(yǔ)很重要。To see is to believe.眼見(jiàn)為實(shí)；百聞不如一見(jiàn)。2. 用作表語(yǔ)動(dòng)詞不定式作表語(yǔ)，常說(shuō)明主語(yǔ)的內(nèi)容、性質(zhì)、特征。The best way is to join an English club.最好的辦法是加入一個(gè)英語(yǔ)俱樂(lè)部。The first thing is to listen to the teacher carefully.首先是要認(rèn)真聽(tīng)老師講課。3. 用作賓語(yǔ)（1）可以接帶to的動(dòng)詞不定式作賓語(yǔ)的動(dòng)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)。We decided to talk to some students about why they go there.我們決定和一些學(xué)生談?wù)勊麄內(nèi)ツ抢锏脑?。He prefers to eat white bread and rice.他更喜歡吃白面包和白米飯。Id love to visitMexico.我想要去參觀墨西哥。（2）動(dòng)詞feel, find, make, think等后面，可以用it作形式賓語(yǔ)代替真正的賓語(yǔ)動(dòng)詞不定式，句子結(jié)構(gòu)是.feel / find / make / . it+adj. / n.+to do.I find it difficult to remember everything.我發(fā)現(xiàn)記住所有事情很難。（3）既可接動(dòng)詞不定式又可接v-ing形式作賓語(yǔ)，意思差別不太大的動(dòng)詞有begin, start, like, love等。一般說(shuō)來(lái)，動(dòng)詞不定式表一次、數(shù)次的具體動(dòng)作、將來(lái)動(dòng)作或動(dòng)作的全過(guò)程，v-ing形式表習(xí)慣性的連續(xù)動(dòng)作。但是這種區(qū)別并不很?chē)?yán)格，特別是美國(guó)英語(yǔ)，即使是習(xí)慣性的動(dòng)作也可以用動(dòng)詞不定式。Then I started to watch TV.然后我開(kāi)始看電視。I am beginning to understand my parents.我開(kāi)始理解我的父母。I like to eat vegetables.我喜歡吃蔬菜。（4）后接動(dòng)詞不定式或v-ing形式作賓語(yǔ)，意思差別較大的動(dòng)詞有forget, remember等。后接不定式作賓語(yǔ)，表動(dòng)作尚未發(fā)生；后接ving形式作賓語(yǔ)，表動(dòng)作已經(jīng)發(fā)生。stop to do停下來(lái)做另外一件事，to do是目的狀語(yǔ)；stop doing停止做、不做當(dāng)前這件事，doing是賓語(yǔ)；try to do盡力做，try doing試試看；go on to do接著做另外的事，go on doing繼續(xù)做原來(lái)的事。When I left home, I forgot to bring it with me.我離開(kāi)家時(shí)，忘記帶上它了。I stopped using them last year.去年，我停止使用它們。4. 用作定語(yǔ)（1）表示將來(lái)。The question to be discussed next meeting is a difficult one.下次會(huì)議要討論的這個(gè)問(wèn)題非常難。（2）當(dāng)被修飾詞是最高級(jí)或序數(shù)詞或被其修飾時(shí)。He is always the first man to come to the office.他總是第一個(gè)來(lái)到辦公室。He is the best man to do the job.他是做這項(xiàng)工作最好的人選。（3）被修飾詞是抽象名詞時(shí)。This is the best way to work out the maths problem.這是解決這道數(shù)學(xué)題最好的辦法。I have a chance to travel to London.我又一個(gè)去倫敦旅行的機(jī)會(huì)。5. 用作賓語(yǔ)補(bǔ)足語(yǔ)（1）帶to的動(dòng)詞不定式作賓語(yǔ)補(bǔ)足語(yǔ)的動(dòng)詞主要有：要求允許提議(ask, allow, , advise)；期望邀請(qǐng)鼓勵(lì)(expect, , invite, encourage)；教導(dǎo)告訴想要(teach, tell, want)；等待希望愿意(wait for, wish, would like / love)。Id invite her to have dinner at my house.我想要邀請(qǐng)她來(lái)我家吃晚飯。We should allow the children to choose their own clothes.我們應(yīng)該允許孩子們選擇自己的服裝。（2）動(dòng)詞不定式作補(bǔ)語(yǔ)，在主動(dòng)語(yǔ)態(tài)句里不帶to，被動(dòng)語(yǔ)態(tài)句里帶to時(shí)，多數(shù)動(dòng)詞是感官動(dòng)詞和使役動(dòng)詞。包括四“看”：look at, observe, see, watch；三“讓”：have, let, make；二“聽(tīng)”：hear, listen to；一“感覺(jué)”：feel；一“注意”：notice。This picture makes me feel excited！這幅畫(huà)使我感覺(jué)很興奮。We saw Liu Yu play baseball last week.上周我們看到劉宇打棒球了。（3）help后接動(dòng)詞不定式作補(bǔ)語(yǔ)，to可帶可不帶。They can help you (to) learn English.他們幫助你學(xué)習(xí)英語(yǔ)。6. 用作狀語(yǔ)（1）目的狀語(yǔ)，置于句首或句末，置于句首時(shí)常表示強(qiáng)調(diào)。In order to catch the early bus, she got up very early.為了趕上早班車(chē)，她起得很早。A group of young people got together to discuss this question.一組年輕人聚在一起討論這個(gè)問(wèn)題。She came to this city to visit her daughter.她來(lái)到這個(gè)城市看望她的女兒。（2）原因狀語(yǔ)，多見(jiàn)于“sb.+be+adj.+to do.”結(jié)構(gòu)句中。I feel very lucky to have him.擁有他我感覺(jué)很幸運(yùn)。（3）結(jié)果狀語(yǔ)，多見(jiàn)于“too.to”，“enough to.”結(jié)構(gòu)句中。Im too tired to do it well.我太累了以至于做不好這件事。The room is big enough for three people to live in.這個(gè)房間三個(gè)人住足夠大。7. 動(dòng)詞不定式的復(fù)合結(jié)構(gòu)動(dòng)詞不定式的復(fù)合結(jié)構(gòu)是“for / of sb. to do sth.”。不定式復(fù)合結(jié)構(gòu)的介詞用for還是of，主要取決于前面形容詞的性質(zhì)。一般說(shuō)來(lái)，of前面的形容詞是careful, clever, foolish, good, kind, nice, wise等，說(shuō)明人的特性；for前面的形容詞是dangerous, difficult, easy, hard, heavy, important, interesting, necessary等，一般說(shuō)明不定式動(dòng)作的特性，前面如果是名詞用for。Its a good idea for parents to allow children to study in groups during the evening.對(duì)父母來(lái)說(shuō)，在晚上讓孩子分組學(xué)習(xí)是個(gè)好主意。Its wise of him to do it well.對(duì)他來(lái)說(shuō)，把這件事做好很明智。8. 帶疑問(wèn)詞的不定式短語(yǔ)動(dòng)詞不定式前面可以帶疑問(wèn)代詞what, which, who或疑問(wèn)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(yǔ)、主語(yǔ)、表語(yǔ)等，或者單獨(dú)使用。要注意的是，why后面的不定式不帶to。（1）用作句子的成分。I dont know what to try next. (作賓語(yǔ))我不知道接下來(lái)要嘗試什么。Where to go is not decided yet.(作主語(yǔ))還沒(méi)有決定去哪里。（2）單獨(dú)使用時(shí)相當(dāng)于一個(gè)特殊疑問(wèn)句。What to do next?=What will we / you do next?接下來(lái)做什么？Why go there?=Why do we / you go there?為什么去那里？9. 動(dòng)詞不定式的否定式不定式的否定式是not / never to do.；不帶to的不定式的否定式是not / never do.They decide not to talk to each other.他們決定不和彼此說(shuō)話。His parents tell him never to play soccer in the street.他父母告訴他不要在街上踢足球。九、動(dòng)名詞（doing）動(dòng)名詞相當(dāng)于名詞,在句子中可以做主語(yǔ)、賓語(yǔ)、表語(yǔ)、定語(yǔ)等。1. 作主語(yǔ)Fighting broke out between the South and the North.南方與北方開(kāi)戰(zhàn)了。2. 作賓語(yǔ)Would you mind turning down your radio a little, please?請(qǐng)問(wèn)你介意調(diào)小一點(diǎn)收音機(jī)的音量嗎?3. 作表語(yǔ)Babysisters job is washing,cooking and taking care of the children.保姆的工作是洗衣服,作飯和照看孩子。4. 做定語(yǔ)a washing machine 一臺(tái)洗衣機(jī)6EDBC3191F2351DD815FF33D4435F3756EDBC3191F2351DD815FF33D4435F3756EDBC3191F2351DD815FF33D4435F3756EDBC3191F2351DD815FF33D4435F3756EDBC3191F2351DD815FF33D4435F3756EDBC3191F2351DD815FF33D4435F375