英语情态动词详解.pptx

情态动词的语法特征 情态动词，在英文中主要用来表示说话人的看法、态度等。从用法上来说，它有这样几个特点：1）各个情态动词自身都有一定的词义。2）不能在句中独立担当谓语，与后面的动词原形合成谓语。也没有非谓语形式。3）情态动词在句中不受任何人称,数变化的影响。4)情态动词后接的不定式（除ought外）都不带to，即接动词原形。英文中的情态动词主要有：can,could;may,might;must;ought;need;dare,dared，另外，shall,will,should,would在一定的场合也可用作情态动词。第1页/共63页1.表示能力,指有能力做某事,译为“能够”。-Can you use chopsticks?-He is only four,but he can read.-In the past,people could not count as we do now.(could表示过去的能力)与be able to的区别:时态can只有现在时和过去时,而be able to有更多形式。can/could的用法的用法 第2页/共63页与be able to的区别:成功地完成某一具体动作,用was/were able to=managed to do/succeeded in doing表示经过一番努力,终于能够完成某事。-The fire spread through the building quickly,but everyone was able to get out.can/could的用法的用法 第3页/共63页区别补充 助动词后只用be able toThey will _ tell you the news soon.他很快就能告诉你消息了。情态动词后只用be able to。They may _ do it.be able to be able to 第4页/共63页考点练兵1.They _tell you the news soon.A.will be able to B can C could 2.The boy _ play the piano very well，when he was seven.A.will be able to B can C could 第5页/共63页2.表示请求或允许,译为“可否”。-Can/Could you turn down the radio?(Could较客气)-You can leave it to me.-He asked me if he could use my mobile phone.回答:Yes,you can.(肯定)No,you cant.(否定)can/could的用法的用法 第6页/共63页3.表示推测,含惊讶、怀疑的语气,只用在疑问、否定、感叹句中。-Its so late.Can Tom be reading?(疑问)-It cant be Mary.She has fallen ill.(否定)-How can you be so careless!(感叹)can/could的用法的用法 第7页/共63页4.cannot too译为“无论怎样也不为过;越越好”。-You cannot be too careful while driving a car on such a dark night.can/could的用法的用法 第8页/共63页1.表示许可。=be allowed to do-You may go now.-May/Might I dance with you?回答:Yes,you may/can.No,you mustnt.may/might的用法的用法 第9页/共63页2.表示推测,只用于肯定句。-She may/might come here tomorrow.(may比might可能性大一些)-They may be still waiting for us.典型例题Peter _B_come with us tonight,but he isnt very sure yet.A.mustB.may C.can D.willmay/might的用法的用法 第10页/共63页3.用于祈使句,表示祝愿。-May you succeed!4.may/might as well用于提出建议,译为“最好”。-You may/might as well stay at home tonight.may/might的用法的用法 第11页/共63页1.表示义务,译为“必须”、“一定要”。-You must hand in your homework.-Must I book the tickets in advance?回答:Yes,you must.(肯定)No,you neednt./dont have to.(否定)must 的用法的用法 第12页/共63页与have to的区别:否定意义不同mustnt表示禁止,译为“不准”、“不允许”。dont have to译为“不必”。-You mustnt smoke in the office.-You dont have to call back tonight.must 的用法的用法 第13页/共63页与have to的区别:时态must没有时态变化,而have to有各种时态。must强调说话人的主观看法,have to强调外在的客观需要,译为“不得不”。-We must obey the traffic rules.-Since it is raining,she has to stay indoors.must 的用法的用法 第14页/共63页 have to有人称、数、时态的变化，而must只有一种形式。He had to look after his sister yesterday.在否定结构中：dont have to 表示不必mustnt表示“禁止”，你不一定要把此事告诉他。_你一定不要把这件事告诉他。_You dont have to tell him about it .You mustnt tell him about it.第15页/共63页2.表示偏要,硬要。-John,must you play the piano at such a late hour?-Who is the girl standing over there?Well,if you must know,her name is Marry.must 的用法的用法 第16页/共63页3.表示推测,只用于肯定句,译为“肯定”。否定为cant,译为“不可能”。现在:must do/must be doing过去:must have done-You have worked hard all day.You must be tired now.-They are playing basketball.They must have finished their homework.must 的用法的用法 第17页/共63页-The door is locked.She cant be at home.(当前推测)-I saw him just now so he cant/couldnt have gone abroad.cant 的用法的用法(过去推测)第18页/共63页must 常考点4在回答带有must 的问句时，否定结构不用mustnt 而用neednt dont have to.-Must I go home?-Yes,_-No _5 表示偏偏，干嘛等责备含义（指做令人不愉快的事情）The car must break down just when we were about to start off.Must you shout so loudly?mustneednt /dont have to.(干嘛 )(偏偏 )第19页/共63页1.表示“应该”。=ought to-You should/ought to work hard.2.should表惊讶,惋惜,译为“竟然”。-I find it astonishing that he should be so rude to you.-I didnt expect that he should have finished the job ahead of time.should的用法的用法 第20页/共63页3.根据经验或事实,合理的推断。-Mary took dancing classes for years;she should be an excellent dancer.-Its said that there are plenty of hotels in that town.There should not be any difficulty for you to find somewhere to stay.should的用法的用法 第21页/共63页1）用于第一人称的构成一般将来时。2)一般用于二、三人称陈述句中，表示命令、许诺、警告、威胁，决心、义务、规定等。You shall have my answer tomorrow He shall be sorry for it one day,I tell you.You shall do as I tell you.Nothing shall stop us from fighting against pollutionEach citizen shall carry ID card when travelling.(允诺)（警告）（命令）(决心)义务、规定shall的用法的用法 第22页/共63页3)用于征求对方的意见和指示，用在一，三人称的疑问句中。Shall I turn on the light?Shall he come to see you?_注：Shall+第三人称主格+do sth =Do you want+第三人称宾格+to do sth.=Do you want him to see you?第23页/共63页1.用于各种人称,表示意志、意愿、请求、自然规律等。-I will tell you the details.-Will/Would you please be quiet?(Would较客气)-If pure water is heated to 100,it will boil.will的用法的用法 第24页/共63页2.表示习惯、倾向,译为“总是”、“惯于”。-He will sit there hour after hour doing nothing.-Every day,the couple would go for a walk in their neighbourhood hand in hand.(过去的习惯)will的用法的用法 第25页/共63页 1）need 的意思是“”需要，既是行为动词，又是情态动词。作形为动词时，他具有一般动词的各种形式，（need、needs、needed、needing）,与助动词（do、does、did）连用构成疑问句和否定句，后面接名词或动词不定式作宾语。作为情态动词，只有一种形式，没有人称和数的变化，后接动词原形，与not 连用时构need not的否定式，疑问句把need提前。need的用法的用法 第26页/共63页1)I need a new computer.2)Your room need painting 3)He doesnt need to work late into the night.4)I need to get a new car.5)Need he work so late?yes,he must no,he neednt.6)you neednt walk that fast,need you?你不必走那么快，是吗？实义动词情态动词实义动词实义动词实义动词情态动词第27页/共63页注意1：need 的被动含义：need,want,require,worth（形容词）后面接doing也可以表示被动：need doing=need to be done注意2：need 作情态动词不用在肯定句中，只用于疑问句和否定句中，第28页/共63页1 它既可以作行为动词又可以作情态动词，作情态动词时，主要用于疑问句，否定句及条件句中，陈述句中很少使用但（I dare say）除外。没人称和数的变化，但有时态变化，过去时为dared.否定式为darent.How dare you say Im unfair?He dare not speak English before such a crowd,dare he?情态动词情态动词dare的用法的用法 第29页/共63页作行为动词时，有时态，人称和数的变化，所不同的是，作行为动词时，在肯定句中，其后常接带to的动词不定式，但在否定句和疑问句中，其后的to 可省可不省。如：I dare to swim across this river.He does not dare(to)answer Dont you dare(to)touch it?第30页/共63页need/dare的用法的用法 情态助动词情态助动词 实义动词实义动词肯定肯定/He dares to escape.He needs to escape否定否定He darent escape.He neednt escape.He doesnt dare(to)escape.He doesnt need to escape.疑问疑问Dare he escape?Need he escape?Does he dare(to)escape?Does he need to escape=can情态动词不用于肯定句。情态动词dare有过去时dared。第31页/共63页1.He _ through the forest alone.A.dare walk B.dare to walk C.dares walking D.dares to walk 2.He hardly _ say anything more,since you know all about it.A.dont need to B.needsC.need D.neednt练一练练一练 情态动词不用于肯定句。情态动词=can第32页/共63页3._ climb that tall tree?A.Would you dare B.Dare you to C.Dare you D.Will you dare 4.Jim _ his strict father,for he failed in the examination once again.A.didnt dare to see B.not dare to seeC.didnt dared to see D.dare no to see练一练练一练 情态动词=Can you行为动词=didnt like to see第33页/共63页情态动词表示推测的用法 can,could,may,might,must 皆可表示推测，其用法如下：1）情态动词+动词原形。表示对现在或将来的情况的推测，此时动词通常为系动词。I dont know where she is,she may be in Wuhan.2）情态动词+动词现在进行时。表示对现在或将来正在进行的情况进行推测。At this moment,our teacher must be correcting our exam papers.第34页/共63页3）情态动词+动词完成时。表示对过去情况的推测。The road is wet.It must have rained last night.地是湿的，昨天晚上一定下雨了。第35页/共63页4）情态动词+动词的现在完成进行时。表示对过去正在发生事情的推测。Your mother must have been looking for you.你妈妈一定一直在找你。5）推测的否定形式，疑问形式用cant,couldnt表示。Mike cant have found his car,for he came to work by bus this morning.迈克一定还没有找回他的车，因为早上他是坐公共汽车来上班的。注意：could,might表示推测时不表示时态，其推测的程度不如can,may。第36页/共63页典型例题1）-Could I borrow your dictionary?-Yes,of course,you_.A.mightB.will C.can D.should 答案C.could表示委婉的语气，并不为时态。答语中of course，表示肯定的语气，允许某人做某事时，用can和 may来表达，不能用could或might。复习：will 与you连用，用来提出要求或下命令。should与you 连用，用来提出劝告。第37页/共63页2）-Shall I tell John about it?-No,you _.Ive told him already.A.neednt B.wouldntC.mustnt D.shouldnt 答案A。neednt 不必，不用。wouldnt 将不,不会的。mustnt 禁止、不能。shouldnt不应该。本题为不需要，不必的意思，应用neednt。3）-Dont forget to come to my birthday party tomorrow.-_.A.I dont B.I wont C.I cantD.I havent 答案B.will既可当作情态动词，表请求、建议、也可作为实义动词表“意愿、意志、决心”，本题表示决心，选B。第38页/共63页14 区别微妙的情态动词练习 情态动词在近年来的高考试题中的难度日渐加大，不仅是由于情态动词表示说话人的语气和心态等，而且这些往往是需用心体会而得的。由于语气的暗示在题目中变得更隐蔽，语气的变化更微妙，因而更综合化了。难点磁场1.()I didnt hear the phone I_ asleep.A.must be B.must have beenC.should be D.should have been2.()We _ last night,but we went to the concert instead.A.must have studied B.might studyC.should have studied D.would study3.()John,you_ play with the knife,you_hurt yourself.A.wont;cant B.mustnt;mayC.shouldnt;must D.cant;shouldnt第39页/共63页4.()Its nearly seven oclock.Jack_ be here at any moment.A.mustB.needC.shouldD.can5.()She_for what she has done,but why do you keep silent on it?A.ought to praise B.ought to have praisedC.ought to be praised D.ought to have been praised6.()If your boss is not right,you_him.A.mustnt obey B.dont have to obeyC.wouldnt have obey D.cant have obey第40页/共63页7.()Shall I call a doctor for you?_.I will be better soon.A.Yes,you may B.No,you mustntC.No,you neednt D.Id rather not8.()Would you like to go shopping with me tonight?_.A.Id love so B.Ill like toC.I would like thatD.Id love to9.()He_ you more help,even though he was very busy.A.might have given B.mightC.may have given D.may give10.()Noise_ harmful in China.A.didnt use to be consideredB.usednt to considerC.didnt use to consider D.isnt used to be considered第41页/共63页案例探究1.Will you stay for lunch?Sorry,_ my brother is coming to see me.A.I mustntB.I cantC.I needntD.I wont2.Sorry Im late.I_ have turned off the alarm clock and gone back to sleep again.(2000年春季高考北京)A.might B.should C.can D.will第42页/共63页 情态动词考查热点透视 情态动词是中高考考查的重点语法项目之一，全国普通高考各地试题对此都有考查。下面就近几年来高考试题中出现的情态动词的考点进行归纳分析，以便同学们复习掌握。第43页/共63页 一、情态动词表推测 1.肯定的推测一般用must,should,may（might）或could（不用can），其中，must的语气最强，译为“肯定”、“准是”、“想必是”；should的语气次之，译为“很可能”、“应该”，指按常理推测；may（might），could的语气最弱，译为“也许”、“可能”。第44页/共63页Helen _ go on the trip with us but she isnt quite sure yet.（2005年安徽卷）A.shall B.must C.may D.can Ive taken someone elses green sweater by mistake.It _ Harrys.He always wears green.（2005年广东卷）A.has to be B.will be C.mustnt be D.could be I have lost one of my gloves.I _ it somewhere.（2005年北京春季卷）A.must drop B.must have dropped C.must be dropping D.must have been dropped If I _ plan to do anything I wanted to,Id like to go to Tibet and travel through as much of it as possible.（2005年湖北卷）A.would B.could C.had to D.ought to 第45页/共63页 2.否定推测分为两种情况：1）语气不很肯定时，常用may not,might not或could not，译为“可能不”、“也许不”。2）否定语气较强时，则用cant，译为“根本不可能”、“想必不会”，表示惊异、怀疑的感情色彩。第46页/共63页 1)You might just as well tell the manufacturer that male customers _ not like the design of the furniture.（2004年上海春季卷）A.must B.shall C.may D.need 2)Do you know where David is?I couldnt find him anywhere.Well.He _ have gone farhis coats still here.（2005年湖北卷）A.shouldnt B.mustnt C.cant D.wouldnt 3)Isnt that Anns husband over there?No,it _ be him Im sure he doesnt wear glasses.（2004年全国卷）A.cant B.must not C.wont D.may not第47页/共63页 3.疑问句中的推测，往往用can或could。Mr.Bush is on time for everything.How _ it be that he was late for the opening ceremony？（2001年上海春季卷）A.can B.should C.may D.must 第48页/共63页 4.对已发生事情的肯定推测常用“must,may,might等+完成式”；否定推测常用“can,could,may,might等+完成式”。1)He _ have completed his work;otherwise,he wouldnt be enjoying himself by seaside.（2005年北京卷）A.should B.must C.wouldnt D.cant 2)Tom is never late for work.Why is be absent today?Something _ to him.（2005年江西卷）A.must happen B.should have happened C.could have happened D.must have happened 3)My sister met him at the Grand Theatre yesterday afternoon,so he_your lecture.（2000年上海卷）A.couldnt have attended B.neednt have atterded C.mustnt have attended D.shouldnt have attended 第49页/共63页 二、“情态动词+完成式”1.“should（ought to）+完成式”表示本应该做某事而实际上没有做。其否定式表示某种行为不该发生但却发生了。Ill tell Mary about her new job tomorrow.You_ her last week.（2004年福建卷）A ought to tell B would have told C must tell D should have told Oh,Im not feeling well in the stomach,I _ so much fried chicken just now.（2002年上海春季卷）A.shouldnt eat B.mustnt have eaten C.shouldnt have eaten D.mustnt eat 第50页/共63页 2.“could+完成式”表示本来能够做成某事的但结果没能做成，含有遗憾的意味。He paid for a seat,when he _ have entered free.（2005年山东卷）A.could B.would C.must D.need第51页/共63页 3.“neednt+不定式的完成式”表示本来不必做某事而实际上做了某事。例如：You neednt have watered the flowers,for it is going to rain.你本不需要浇花的，因为天就要下雨了。Catherine,I have cleaned the room for you.Thanks.You _ it.I could manage it myself.（2005年福建卷）A.neednt do B.neednt have done C.mustnt do D.shouldnt have done 第52页/共63页 三、常见的情态动词 1.shall用于一、二、三人称疑问句表示征求对方意见；用于二、三人称陈述句表示说话人给对方的命令、警告、允诺或威胁等。“The interest be divided into five parts,according to the agreement made by both sides，”declared the judge.（2004年重庆卷）A.may B.should C.must D.shall Excuse me,but I want to use your computer to type a report.You _ have my computer if you dont take care of it.（2004年湖南卷）A.shant B.might not C.neednt D.shouldnt The room is so dirty._ we clean it?Of course.（2003年北京春季卷）A.Will B.Shall C.Would D.Do 第53页/共63页 2.must用于疑问句，表示责备、抱怨的感情色彩，意思为“偏偏，偏要”；mustnt表示禁止，是说话人强有力的劝告。John,look at the time._ you play the piano at such a late hour？（2005年全国卷）A.Must B.Can C.May D.Need Tom,you leave all your clothes on the floor like this！（2005年全国卷）A.wouldnt B.mustnt C.neednt D.may not 第54页/共63页 3.neednt表示“没有必要”。Lucy doesnt mind lending you her dictionary.She _.Ive already borrowed one.（2005年湖南卷）A.cant B.mustnt C.neednt D.shouldnt 第55页/共63页4.would表示过去反复发生的动作或某种倾向。When he was there,he _ go to that coffee shop at the corner after work every day.（1996年上海卷）A.would B.should C.had better D.might 第56页/共63页 5.表示经过努力而成功的某一次动作，只能用was/were able to，而不能用could。The fire spread through the hotel very quickly but everyone _ get out.（1997年全国卷）A.had to B.would C.was able to D.could 第57页/共63页 6.考查情态动词用作答语的情况 Write to me when you get home._.（2001年北京春季卷）A.I must B.I should C.I will D.I can Could I call you by your first name？Yes,you _.（1998年上海卷）A.will B.could C.may D.might 第58页/共63页情态动词过关检测题情态动词过关检测题 第59页/共63页1.-Tom graduated from college at a very young age.-Oh,he _ have been a very smart boy then.A.could B.should C.might D.must 2.“The interest _ be divided into five parts,according to the agreement made by both sides,”declared the judge.A.may B.should C.must D.shall 3.-Ill tell Mary about her new job tomorrow.-You _ her last week.A.ought to tell B.would have told C.must tell D.should have told 4.-Excuse me,is this the right way to the Summer Palace?-Sorry,I am not sure.But it _ be.A.might B.will C.must D.can 5.I _ pay Tracy a visit,but I am not sure whether I will have time this Sunday.A.should B.might C.would D.could 第60页/共63页6.-I dont mind telling you what I know.-You _.Im not asking you for it.A.mustnt B.may not C.cant D.neednt7.I often see lights in that empty house.Do you think I _ report it to the police?A.should B.may C.will D.can 8.Mr White _at 8:30 for the meeting,but he didnt show up.A.should have arrived B.should arrive C.should have had arrived D.should be arriving 9.-Isnt that Anns husband over there?-No,it _ be him-Im sure he doesnt wear glasses.A.cant B.must not C.wont D.may not 10.You _be tired-youve only been working for an hour.A.must not B.wont C.cant D.may not 第61页/共63页 Thank you第62页/共63页感谢您的观看！第63页/共63页