常考语法结构讲解2003.doc

常考语法结构讲解一、时态1一般现在时1.1 一般现在时可以用在条件状语从句和时间状语从句中表示将来时间。例如：We shall go outing when you finish your holiday homework.1.2 表示按规定、计划或安排要发生的情况，常用于口语中，句中常有一个表示时间的状语。主要用于be, come go, start, begin, leave, return, end ,stop, open, take place等系动词。例：The plane takes off at 11 a.m.飞机上午11点起飞。They leave at nine tomorrow morning.他们明天上午9点钟离开。1.3 一般现在时除了可以用在时间状语从句和条件状语从句中表示将来时间外，还可用在wh-从句中，表示将来时间。例：It doesnt matter who goes first.Whatever you say, I wont change my mind2一般过去时当主句为过去将来时，在其时间状语、条件状语从句中用一般过去时表示过去将来的动作，例：I would not go with you if it rained the next. 3现在进行时3.1.在时间状语从句或条件状语从句中表示将来正在进行的动用。例：Wake me up if Im still sleeping at 7.Take care when you are walking.3.2.表示一个在最近按计划或安排要进行的动作（这时多有表示未来的状语）。例：Are you going anywhere tomorrow?We are leaving on Friday.注：这种情况仅限于go, come, leave, start, arrive, return, work, sleep, stay, play ,have, wear等动词。3.3.表示状态、感觉等的动词，如be, love, like, know, forget, hope, see, belong to, own ,consist of, hate, want, prefer, understand, doubt, remain, contain, suggest, possess, desire等，一般不能用于进行状态，因为它们不能表示正在进行的动作，若用于进行时态，则表示重复的动作，往往带有说话人的感情色彩，常与always, constantly, continuously, forever等词连用；或该动作已接近完成，或词义已发生转换。例：He is always changing his mind. The train is arriving.He is expecting (waiting for )his girlfriend.4现在完成时4.1.在用already, yet, just, as yet, ever, never等副词做状语时，常用现在完成时。4.2.如果表示动作发生在过去，完成在过去，但与现在情况仍有联系，或者其影响、结果仍然存在，此时不与表示一般的状语连用。例：We have visited the Summer Palace.4.3.如果表示动作发生在过去，持续到现在才完成或有可能继续下去，则通常与表示一段时间的状语连用。其中由since引导的状语从句用一般过去时。例：Richard has been ill for about 2 weeks since she left.4.4. 如果主句是一般将来时，由as soon as , after, before, till/until, when, if等引出的状语从句常用现在完成时表示将来完成的动作。例：Ill help you as soon as I have finished my homework.4.5.在下面这些表达方式后面要用现在完成时：This (That/It) is the first (second/third, etc,)This (That/It) is the only.This (That/It) is the best (finest/worst/most interesting etc)That is the first time( that) he has felt relaxed for months.That is the fourth bottle (that ) they have drunk this evening.Its one of the most wonderful films (that) Ive ever seen.如果主句动词表示的是过去时间，从句通常用过去完成时；如果主句动词表示的是将来时间，从句动词仍然用现在完成时。例：It was the third time that he had got drunken.Itll be the first time that the student has written a paper. 4.6.瞬时动词（Punctual verb）用于完成体时，其肯定式不能和时间段连用，即不能和表示一段时间的in the past/last few years, for three days, by/up to now, since, so far 等时间状语连用。如我们不能说：They have come here for half a year.但是，瞬时动词的否定式可以和时间段连用。例：We havent seen each other for over ten years. 我们已有十年多没见面了。We have seen each other for over ten years.(误)常见的瞬时动词有：ask, begin, buy, come ,decide, go, hear, leave, lose, meet, recover, return, see, stop, talk, visit等。5过去完成时过去完成体的特殊用法：5.1.用于hardly/scarcelywhen和no soonerthan 句型中。例：I had hardly entered the house when it began to rain.Hardly had I entered the house when it began to rain.I had no sooner entered the house than it began to rain.No sooner had I entered the house than it began to rain.5.2.动词hope, expect, think, intend, mean, want, suppose, plan等用过去完成体，表示未实现的愿望、打算和意图。例：I had thought that you could come and visit us.I had meant to come, but I was too busy.6现在完成进行时表示动作从过去某一时刻开始，一直持续到现在，可能刚刚停止或正在进行，强调动作延续的长外。例：He has been working there for 5years.My daughter has been writing letters all afternoon and she has not finished yet.7.过去完成进行时过去完成进行时表示动作从过去某一时刻开始，一直持续到过去另一时刻，那时动作可能刚完成，也可能仍在进行。它与过去完成时的不同之处在于强调动作的长久性。例：I had been looking for it for hours before I found it.It had been raining for two days. The fields were all under water. 8将来时8.1.一般将来时有多种表示形式，如“will/shall+动词原形”，“be going to+动词原形”，“be to +动词原形”，“be about to +动词原形”。其中will/shall泛指将来；be going to 指人时着重于打算，指事时表示有迹象要发生的情况；be to 表示按计划、安排要发生的动作；be about to 表示即将发生的动作。8.2.将来进行时表示将来某时刻一定发生某动作或某动作正在进行。例：At 10 a.m. tomorrow, well be waiting for you at the station.8.3.将来完成时表示将来时刻完成的动作，一般有表示将来某时刻的时间状语，如by the time, by the end of, when等引出的时间状语。例：By the end of this semester, I shall have completed 4 courses.Call me at 6 this afternoon. Ill have finished my dinner by then.8.4.将来完成进行时表示一个一直持续到将来某一时间的动作，那时可能还要进行下去。例：We shall have been working for 15 years in university by the end of this year.8.5.过去将来时指从过去某一时间开始将要发生或可能要发生的动作。例：Tom said he would arrive here at 5. 二、主谓一致一致是指句子成分之间或词语之间必须在人称、数、性等方面保持一致关系。英语中最主要的一致关系是主谓一致。在处理一致关系的问题上必须遵循以下三个原则：a语法一致从语法形式上取得一致，如主语为单数形式，谓语动词也用单数形式；主语为复数形式，谓语动词也用复数形式。b意义一致从意义着眼来处理一致问题。如有时主语形式上虽为单数，但其意义为复数，谓语动词也采用复数形式。c就近原则谓语动作的人称和数往往同和谓语靠得最近的主语人称和数保持一致。1单、复数同形的名词作主语。（1）熟记单、复数同形的名词，特别是以-s结尾的单、复数同形名词：sheep, deer, aircraft, crossroads, headquarters, means, species, series, works等。（2）根据句中出现的限定词（a/an, many, a few, several, this/that, these/those, every, each, all等）或代词确定其单、复数。（3）根据“意义一般”原则判断。Every means has been tried since then. 2只能用作复数的集体名词。这些名词包括：cattle, people, police, folk, poultry 等。例：The cattle were grazing on the meadow. 3既可做单数也可做复数的集体名词。（1）根据“意义一致”原则判断。（2）记住常用的此类名词:army, board, family, committee, couple, crowd, crew, jury, staff, team, public, government 等。例：My family have agreed not to exchange gifts this year.The government has imposed a ban on demonstrations.4.表示学科或疾病的名词作主语。以-s结尾的学科或疾病的名词做主语，谓语动词用单数形式。常用的名词有：economics, electronics, physics, mechaincs, diabetes, mathematics, optics, politics, statistics, measles等。5and 连接两个并列名词作主语。and 连接两个或两个以上单数名词作主语，指同一个人、同一事物或同一概念时，谓语动词必须用单数，判断标志为：并列的单数名词共用一个限定词。如果分别表示不同的人、物或概念时，谓语动词用复数，判断标志为：并列的单数名词前分别有限定词。6连词引导并列成分作主语。（1）根据“邻近一致|的原则判断。（2）bothand 引导主语，谓语动词只能用复数形式。（3） or, eitheror,neithernor, not only but also.，等连词引导的并列主谓，根据“邻近一致”的原则，应以第二个主语的人称数来确定谓语动词的形式。7下列短语作主语，其谓语动词的形式视of后名词的数而定（即可数名词为复数，物质名词或抽象名词为单数）。a lot of ,all of, some of, most of, half of, two thirds of, 90% of , part of ,the rest of等。例：Some of the coins (money) were (was) missing. 8.由下列介词引起的短语跟在主语后不影响主语的数。Accompanied by, along with, as well as, but, except, in addition to, including, instead of, like, more than, rather than, together with等。例：The president of the college, together with the deans, is planning a conference for the purpose of laying down certain regulations. 9.下列名词均为不可数名词，需牢记谓语动词用单数形式。Advice, equipment, furniture, information, luggage, news, behaviour, cash, clothing, fun, knowledge, luck, machinery, lightning, thunder, traffic, weather等。 10分类词作主语（1）记清常用分类词：sort, kind, form, piece, portion, quantity, series, section, species, type等。（2）“分类词+of+名词”作主语，谓语动词的单、复数与分类词一致。11数词和表示时间、金钱、度过量衡、温度等名词作主语，表示一定的量或总量时，谓语动词一般用单数形式。Fifteen minutes is all that I can spare to talk over this matter with you. 12. “there be”结构的主谓一致。依据“邻近一致”的原则判断，根据紧跟be后面的这个名词的数来确定be的半日、复数形式。13定语从句中的主谓一致根据定语从句修饰的先行词的人称、数来判定定语从句谓语动词的人称、数。应当引起高度重视的是，在“the only one of+复数名词或代词”结构中，定语从句修饰the only one，从句谓语动词用单数；而在“one of+复数名词或代词”的结构中，定语从句修饰复数名词或代词，从句的谓语动词用复数。例：Jane is one of those people who like cross-talks.He is the only one of the students who has finished the assigned work. 三、反意疑问句1当主句以suppose，think, believe, expect等动词作谓语，并且主句的主语是第一人称时，句末的反意疑问部分与宾语从句一致。当否定转移到此类句子的主句时，反意疑问部分用肯定的形式。例：I dont suppose he is serious, is he?I suppose youre not serous, are you?2.当句子主语是anything, everything, nothing, something等指物的代词时，反意疑问部分的主语用it；当句子的主语是anyone, somebody, everybody, on one, nobody等指人的代词时，反意疑问部分的主语常用they。3当陈述部分是“I am”时，反意疑问部分要用arent I; 但反意疑问部分是肯定形式时，可用am I。I am not your student, am I?/I am your student, arent I?4.在反意疑问部分中一般不用maynt ，常用mightnt或cant 代替，表示将来情况还可以用wont.They may be here next week, mightnt they?（此处也可用wont they）5.在含有情态动词的反意疑问句中，有几点应注意：5.1.used to 的否定形式：usednt to, didnt use to，因此反意疑问部分用didnt+主语或usednt+主语.5.2. there used to be5.3.在带有had better(最好)，would rather(宁愿)，would sooner(宁愿)，would as soon(宁愿)，would like(想)等的句子中，反意疑问部分以had, would 为助动词。例：We had better go, hadnt we?Youd rather stay here alone, wouldnt you?5.4.应注意dare 和need作实义动词和作情态动词的不同情况下，应作出不同的反问。例：He dares to escape, doesnt he?(行为动词)He darent escape, dare he?(情态动词) 5.5.在有ought to 的句子中，反意疑问句多用shouldnt。例：We ought to go now, shouldnt we?5.6.陈述部分含有表示推测的情态动词must时，若must+be用来对现在情况进行推测，可当作一般现在时或现在进行时的反意疑问句处理。例：You must be very hungry, aren t you?He must be working at the office, isnt he?5.7.must+完成体用表示推测过去的动作持续到现在，按完成体的反意疑问句来处理。You must have studied English for years, havent you?5.8.must+完成体用来表示对过去情况的推测，可当作一般过去时的反意疑问句处理。You must have come last week, didnt you? 6.含祈使句的反意疑问句（1）当let us 或let me 表示请求许可时，不可缩略成lets,反意疑问部分用“will you?”。当表示建议时，可用lets，反意疑问部分用“shall we?”。（2）肯定祈使句的反意疑问分部常用will you 表示请求，用wont you 表示提醒对方注意，用can you 表示告诉某人做某事。例：Stop talking, can you?Have some coffee, wont you?(3)祈使句陈述部分如果是否定的，反意疑问部分一般用肯定的“will you”。例：Dont make a noise, will you? 7.带有感叹语气的反意疑问句感叹句的反意疑问句一般都是否定的反问：“isnt it?”/isnt he?”等等，动词一律用“be”。8陈述部分的主语是指示代词this 或that，附加部分的主语用it。当主语是these 或those时，附加部分的主语用they。9并列复合句的反意疑问部分，谓语动词根据邻近的分句的谓语动词而定。例：He is a professor, but his lady is an actor, isnt she?10.陈述部分的主语是不定式（短语）或动名词（短语），疑问部分的主语用it。例：Swimming is great fun, isnt it?11None of+不可数名词，疑问部分用肯定式，主语用it；none of+可数名词，根据情况分别选用they, you 或we。12若陈述部分所含的否定词是通过前缀或后缀而构成的，其后的附加部分仍然用否定结构。例：Its unfair, isnt it?You are hopeless, arent you? 四、情态动词1.情态动词+行为动词完成体，表示对过去的推测和评论。Must+have+done表示“一定发生了”。Can not /could not+have +done表示“一定没发生”。Could/may/might+have+done表示“很可能”、“或许发生了”。Should/ought+to+have+done表示“本来应该而实际未发生”，其否定则表示“本不该而实际上已发生了”。Neednt+have+done表示“本来不必而实际上已发生了”。情态动词+不定式完成进行体，表示推测过去某动作是否正在或一直在进行。例：She must have been working then. 2某些情态动词的特殊用法2.1.need情态动词need没有人称、数的变化，本身没有时态变化，后接动词原形。其肯定式只能用于疑问句，在其他句型中必须用其否定式neednt 或need not。实义动词need有人称、数与时态变化。如果动词不定式做宾语，必须是带to的不定式（有主动、被动两种形式，而动名词V-ing只有一种形式）。其否定形式为助动词+not+need。例：“My overcoat needs washing.”“Send it to the laundry, You dont need to wash it yourself.” 2.5.Would, used towould+V和used to+V都可表示“过去经常”、“过去惯常”的意思。Used to 还可以表示过去的一种状态，而would则不可以。used to 后可接动态动词或状态动词，而would后只能跟动态动词。2.6.used to+V,be used to+V-ing, be used to+V used to V是“过去常”、“过去一直”的意思：be used to V是“用来”的意思；而be used to V-ing则是“习惯于”的意思。used to 只表示过去，而be used to 则可表示过去、现在或将来。2.7.will(表示“愿意”、“倾向”)，will not(表示“拒绝”)If you will allow me, I will see you home.A man who wont work is no good. 五、倍数表示法1. times+as+形容词/副词原级+as(是/为的倍)。例：This bridge is 4 times as long as that one.Last year, Mickey earned twice as much as his brother.2. times+that/(the +名词)+of（是/为的倍）。例：The mass of a hydrogen is 1840 times that of an electron.The earth is 49 times the size of the moon.The new runway for jet planes is 4 times the length of the one constructed 15 years ago.注意：“the+名词”中的名词指size, length, weight, amount等与“量”有关的词。3. times+比较级+than（是/为的倍）。例：The productivity has been 4 times greater than usual.Some computers can work 500,000 times faster then any human being.4. 用倍数动词double, triple, quadruple(+名词)分别表示增加一、二、三倍。例：The efficiency of the machines has been more than tripled.5.增加到倍，用表示增加的动词+to+times.例：Last year profits rose to three times. This year the value of our industrial output has increased to twice that of last years.6. 表示 “增加了倍” 。表示增加的动词（如increase, raise, rise, go up）+by +times.例：The output has gone up by five times. 六、强调句型1 强调句型It is/was. that/who所强调部分可以是人或物，即主语或宾语当被强调部分是人时可以用who或that；当被强调部分是物时则用that。2 强调句型的强调部分也可以是状语，如时间状语、地点状语、方式状语，或由because引导的原因状语从句。由though 和although引导的状语从句一般不做强调部分。强调状语时，被强调部分后必须用that。例：It was in London that I first met John.3 可以强调疑问句中某一部分。例：Was it yesterday that he gave Mary a handbag?4 强调谓语动词用do/does/did。例：Philip did work very hard last month.5 用“whatis/was+”表示强调。“whatis/was+”型强调句的主语通常是由what引导的主语从句，从句的谓语是动词do（被强调部分）的一种形式。当do为现在时、过去时或将来时，主句表语通常是带to的或不带to的动词不定式短语。例：What he does is (to) to over his lessons.What he is going to do is (to) go over his lessons如果what从句中谓语do 以-ing分词形式出现，主句的表语也采取-ing分词短语形式。例：what he was doing was making a plan.What he is doing is making a plan. 6 如果句子的主语不是代词，我们可以把句子的表语连同系动词be一起提至主语前面以表示强调。例West of our city is a reservoir.Lying on the floor was a boy aged bout seventeen.7 为了强调，使叙述更生动，我们可以把一些表示方位的状误提至唏首，同时将谓语也提至主语之前，若主语是人称代词，谓语仍然放在主语之后。例：Up and up went the prices.Lower and lower they bent.8 在带有as和though的结构中，可将形容词提前，形成“形容词+as/though+主语+主谓”句型，以表示强调。例：Powerful though these officials may appear, they are actually very weak.Cold as it was, we went out.Tried as she was, she went to working. 七、非谓语动词1不定式和动名词作主语1.1.不定式作主语的句型It is +n.+to do(代不定式)It takes sb.+some time+to doIt is +adj.+for sb.+to doIt is +adj.+of sb.+to doIt is our duty to help them.帮助他们是我们的责任。1.2.动名词作主语句型It is +no use, no good ,fun, a great pleasure, a waste of time, a bore等名词+doing sth.It is +useless, nice, good, interesting, worthwhile, pointless, expensive等形容词+doing sth.There is no +doing (there is no 表示“不可能”)1.3.不定式和动词作主语的区别动名词作主语通常表示抽象动作；而不定式做主语表示具体动作。例：Smoking is prohibited here.这里禁止抽烟。（抽象)It is not very good for you to smoke so much.你抽这么多烟对你身体很不好。（具体）动名词作主语时，通常用以表示一件已知的事或经验。不定式短语作主语通常用来表示一件未完成的事或目的。例：Climbing mountains is interesting.爬山很有趣。（经验）Driving a car during the rush hour is tiring.在交通高峰时开车令人厌烦。（经验）To study abroad has long been my dream.长久以来，出国念书一直是我的梦想。（一件尚水完成的事情）2不定式、动名词和分词作表语2.1.不定式作表语时，主语通常是一个名词、不定式短语或者从句，不定式作表语一般表示动作，特别是表示将来的动作。例：Your present task is to learn English well.你当前的任务是把学好。To treat comrades like enemies is to go over to the side of the enemy.把同志当敌人看待就是投降敌人。What he wanted was to get the work done as quickly as possible.他所想的是使工作尽快做完。2.2.动名词作表语动名词作表语，表示抽象的一般性的行为。例：Our work is serving the people.我们的工作是为人民服务。His hobby is collecting stamps.他的爱好是集邮。注意：动名词作表语时与进行进态中的现在分词形式相同，但其所属结构不同。进行时态中的现在分词说明动作是由主语完成的。动名词作表语，说明主语的性质或情况。2.3.分词作表语表示心理状态的动词如excite, delight等都是及物动词。汉语注解不是“激动”、“高兴”，而是“使激动”、“使高兴”。因而现在分词应该是“令人激动的”、“令人高兴的”，过去分词则是“感到激动的”和“感到高兴的”、“令人高兴的”，过去分词则是“感到激动的”和、感到高兴的”。所以，凡表示“令人的”都是-ing形式，凡是表示“感到的”都是-ed形式。这类词常见的有：interesting使人感兴趣的interested感兴趣的exciting令人激动的excited感到激动的delighting令人高兴的delighted感到高兴的disappointing令人失望的disappointed感到失望的encouraging令人鼓舞的encouraged感到鼓舞的pleasing令人愉快的pleased感到愉快的puzzling令人费解的puzzled感到费解的satisfying令人满意的satisfied感到满意的surprising令人担心的surprised感到担心的Traveling is interesting but tiring.旅行是有趣的，但却是使人疲劳的。The pupils will get confused if they are to learn much.如果要学生学得太多，他们会感到糊涂的。The argument is very convincing. 这个论点很令人信服。They were very excited at the news.听到这个消息，他们非常激动。3不定式、现在分词和过去分词作定语3.1.不定式作定语3.1.1不定式可以作为定语修饰以下几类名词：由动词派生或者转化而来的名词。这类名词有：agreement, attempt, claim, decision, desire, determination, failure, need, plan, intention, promise, refusal, resolution, tendency, wish threat.例：His wish to buy a car came true.他要买辆车的愿望实现了。Their decision to give up experiment surprised us. 他们放弃这个实验的决定使我们大吃一惊。由可以与不定式搭配的形容词派生出来的名词。这类名词有：ability, ambition, anxiety, aptitude, (im)patience, reluctance, (un) willingness等。例：She was obviously eager to learn dancing.Her eagerness to learn dancing was obvious.显然她急切地想学跳舞。She was curious to know the end of story.She was burning with curiosity to know the end of the story.她很想知道事故的结局。某些抽象名词，如：chance, effort, opportunity, place, reason, right, time, way等。例：the right to speak, the time to go to bed, the reason to fire him, the effort to rescue the wrecked boat, the chance to win the game, the ability to do the work, the way to get to the station.3.1.2.不定式作为定语还可以用以修饰这几个代词：something, anything, nothing, everything.例：I have something to tell you.我有事情告诉你。He has everything to lose and nothing to gain.他失去了一切，什么也没得到。There is nothing to worryh about.没有什么值得发发愁的。3.1.3.由only, last, next等序数词或形容词最高级修饰的名词后常用不定式作定语。例：He is always the last one to leave the classroom.他总是最后一个离开教室。I dont think he is the best man to do the job.我认为他不是做这个工作的最佳人选。Tom is the only student to answer the question correctly in his class.汤姆是班里面惟一一个正确回答问题的学生。You are the first to undertake the blood test.你是第一个参加验血的。3.1.4不定式常常用于修饰have, give, get, look, for, find等具有“得到”、“有”等意义的动词的宾语。例：Jack has a large family to support.杰克有一大家子人要养活。She has given me much to think about.她给了我很多可以思考的东西。He has found a room to live in.他已经找到了一间房子居住。She has a lot of work to do in thd morning.早上她有很多工作要做。 3.1.5不定式常常作定语用于there be结构的真正主语。例：There are many difficulties to overcome.有很多困难有待克服。There is a big task to complete.有项重大任务有待完成。3.1.6不及物动词构成的不定式作定语，要加适当的介词，和被修饰的名词形成逻辑上的动宾关系，这里的介词不能省去。例：I need a pen to write with. 我需要一支笔写字。3.2.分词作定语分词做定语时有下面几个特点：现在分词表示主动意义，过去分词一般表示被动含义。现在分词表现正在进行，过去分词状态或做完（完成）的事。例：He rushed into the burning hours.他冲进了正在燃烧的房子。The child standing over there is my brother.站在那儿的男孩子是我的弟弟。The room facing south is our classroom.朝南的房间是我们的教室。Have you got your watch repaired? 你的表拿去修理了吗？He is an advanced teacher.他是个先进教师。3.3.不定式和分词作定语时的时间关系一般来说，不定式所表示的动作发生在谓语动词所表示的动作之后；现在分词所表示的动作与谓语动词所表示的动作同时发生；过去分词表示的动作发生在谓语动词所表示的动作之前。例：Do you want to see the doctor to be sent for from Beijing?你要见那位将从北京主动来的医生吗？Do you want to see the doctor working on the case report in the office?你要见那位正在办公室里写病历的医生吗？Do you want to see the retire doctor?你要见那位退休的医生吗？4不定式和动名词作宾语4.1.不定式作宾语4.1.1.有些动词只可以用动词不定式作宾语。这些动词有：afford, agree, arrange, ask, attempt, claim, dare, decide, demand, decline, desire, determine, endeavor, expect, guarantee, pretend, happen, hope, learn, long, love, manage, mean, offer, plan, pledge, prepare, want, refuse, promise, resolve, seek, strive, threaten, undertake, volunteer vow, help, wish4.1.2.在有些复合宾语中，it常常被用来代替不定式作形式宾语，而把不定式放在句尾。可以这样使用的形式词有：necessary, possible, impossible, difficult, easy,natural, hard.可以这样使用的动词有：consider, judge, make, think, find等。I found it difficult to pass the exam held by the professor.我发现很难通过这位教授举行的考试。They consider it impossible to clime over such a stiff precipice.他们认为翻越这样一座峭壁是不可能的。4.1.3.有些动词后可以接“疑问句+不定式”结构作宾语，这样的动词有：know, ask, explain,wonder, learn, study,find out等。例:He knows where to find the treasure.他知道到哪儿去找财宝。We learn how to manufacture this so