Modal Verb情态动词情态动词表示说话人的情态动词表示说话人的语气语气和和情态情态的动词。的动词。语气语气：能力、义务、建议、允诺、：能力、义务、建议、允诺、许可、推测。许可、推测。情态情态：情感和态度。：情感和态度。观察下列各句，注意谓语动词形式。1.He can finish the paper in an hour.2.Would you please pass me the dictionary?3.She may be very busy now.4.I will never forget the days we spent together.5.We should help each other.情态动词的语法特征1.不能单独做谓语，即是情态动词不能单独做谓语，即是情态动词+动词原形。动词原形。 例如：例如：I can swim.（谓语）（谓语） (除除ought to “应该应该”和和have to“不得不不得不”外外) 2.情态动词没有人称，数的变化。情态动词没有人称，数的变化。3.有些情态动词有一般式和过去式，过去式比一有些情态动词有一般式和过去式，过去式比一般式更委婉。般式更委婉。 如如can-could , will-would, may-might, shall-should建议,请求,允许,能力1.Jimisntgoodatmaths,buthecanspeakEnglishwell.2.MayIhavealookatyourIphone?3.Wouldyouliketojoinmyfamilyfordinner?4.Whengoingbyplane,youshouldarriveontime.5.Whenyoueatfish,youmustbeverycarefulwiththebones.能力能力请求请求/允许允许请求请求建议建议建议建议情态动词语法目录 一、一、can/could二、二、may/might三、三、will/would四、四、shall/should五、五、must 1.I can/ am able to swim.2.I could/ was able to climb a tree when I was a child.3.I will be able to swim next week.4.The fire spread through the hotel very quickly but everyone was able to get out 1. can 表示现在的能力表示现在的能力2. could表示过去的能力表示过去的能力3. be able to 表能力，可用于多种时态表能力，可用于多种时态4. be able to 强强调某人通过努力克服调某人通过努力克服困难成困难成功地做了某事功地做了某事一、一、情态动词表能力情态动词表能力2.表表“许可许可”，译为，译为“可以可以”，could比比can语气较委婉。用语气较委婉。用can或或cannot/cant回答回答-Can/CouldIborrowyourbikeforamoment?-Yes,youcan./No,youcant.3.表表“可能性可能性”，译为，译为“可能可能”；Canthisnewsbetrue?Wherecantheybe?否定句中，翻译为否定句中，翻译为“不可能不可能”Shecanthaveleftschool,forherbikeisstillhere. 情态动词情态动词 含义含义否定式否定式 注意点注意点can / could表能力表能力“能，会能，会”cant“不会，不能不会，不能”区别区别 be able to表许可表许可“可以可以”cant “不可以，不许不可以，不许”代替代替may表推测表推测“可能可能”cant “不可能不可能”主要用于主要用于否定、否定、疑问句疑问句中中1表示某人通过努力克服困难做成某事表示某人通过努力克服困难做成某事,要用要用was / were able to.2 could, might, would 表委婉语气用于疑问句表委婉语气用于疑问句, 答语仍须用答语仍须用 can, may, will.3 can 用于肯定句中用于肯定句中, 可表示可表示”有时可能有时可能”情态动词情态动词 含义含义否定式否定式 注意点注意点can / could表能力表能力“能，会能，会”cant/couldnt“不会，不能不会，不能”区别区别 be able to表许可表许可“可以可以”cant /couldnt“不可以，不许不可以，不许”表推测表推测“可能可能”cant /couldnt“不可能不可能”主要用于主要用于否定、疑否定、疑问句问句中中补充：金版补充：金版12页右边第页右边第4点点May I eat KFC if I finish my homework?may/might:1. 表示许可。表示请求、允许时，表示许可。表示请求、允许时，might比比may的语气更委婉一些。的语气更委婉一些。 Might/MayIuseyourcomputer?Yes,youcan./No,youcant/youmaynot/youmustnt. may/might:2.用于祈使句中表示祝愿。用于祈使句中表示祝愿。3.表示推测、可能（只用于肯定句，表示推测、可能（只用于肯定句，疑问句则要用疑问句则要用can或或could）。）。 祝你成功！祝你成功！ May you succeed. He may be very busy now. May you be happy all your life. 情态动词情态动词 含义含义否定式否定式may/might表表许可可“可以可以”mustnt不不许，严禁禁maynot最好不要最好不要表推表推测“可能可能”maynot可能不可能不will和和would1.Willyougivehimamessagewhenyouseehim.用于第二人称，表用于第二人称，表“询问意愿，提出意愿，提出请求求”wouldyou(用于用于现在在时)语气更气更为婉婉转2.Wewillhelphimifheasksusto.表表“意志，意愿意志，意愿”，译为“会会”过去去时：wouldIpromisedthatIwoulddomybest.3.Hewillalwaystakeawalkaftersupper.习惯上会上会发生的事情生的事情Duringthevacationhewouldoftenvisitme.(过去式过去式)4.某种特定情况下真实或可能的事情某种特定情况下真实或可能的事情Atthattime,peoplewouldstarveiffoodwasdifficulttofind.情态动词情态动词 用用 法法will1.表请求表请求(第二人称第二人称)2.表意志表意志,意愿意愿3.表某种表某种倾向或倾向或习惯习惯4.某种特定某种特定情况下真实情况下真实或可能的事或可能的事情情would更客气的更客气的请求请求过去的意志过去的意志,意愿意愿过去的过去的倾向或倾向或习惯习惯过去某特定过去某特定情况会发生情况会发生的事情的事情shall:1.Shall用于第一、第三人称疑问用于第一、第三人称疑问句中，表示说话人征求对方的意句中，表示说话人征求对方的意见、向对方请示或提供帮助见、向对方请示或提供帮助 。1.Shallwebeginourlesson?2.Whenshallhebeallowedtoleavehospital?3.ShallIcarrythisbagforyou?shall:2.Shall用于第二、第三人称，表用于第二、第三人称，表示说话人给对方命令、警告、允示说话人给对方命令、警告、允诺或威胁。诺或威胁。 Youshallfailifyoudontworkharder.Heshallbepunishedaccordingtotherule.HeshallhavethebookwhenIfinishit. 警告警告威胁威胁允诺允诺should1.Youngpeopleshouldrespectoldpeople.should表表“义务，建，建议”。2.Itsfiveoclock.Johnshouldbeathomenow.表推表推测，按道理，按道理应当。当。译为“理理应，估，估计Wehavepreparedafridgeofgoodanddrinks.Thatshouldbeenoughfortheparty.3.表示表示“竟然竟然”Itsapitythatheshouldbesorudetoalady.情态动词情态动词 用用法法shall征求征求对方意方意见(第一第一,三人称三人称)表示命令表示命令,警告警告,威威胁或允或允诺should/oughtto表示表示劝告告,建建议,命令或命令或责任任“应该,必必须”表示推表示推测,“理理应,估估计,大概大概”should还可表示可表示“竟然竟然”must 表“必须” dont have to dont need to neednt Must we hand in our exercisebooks today? Yes,you must/ No,you dont have to 2.1. 不必须不必须mustnt 禁止2.表表“推推测”时：肯肯:mustbe+表语表语(一定一定）否否:cant(不可能不可能)e.g.ThatcantbeMary.SheisinNewYork.3.haveto“不得不不得不”，表客，表客观需要需要情态动词情态动词 含义含义否定式否定式注意点注意点must表必要表必要“必须必须”neednt“不必不必”( 区别区别 have to)有时表有时表“偏要偏要”表推测表推测“一定一定” cant“不可能不可能”只能只能用于用于肯定肯定句，句，不能不能用于用于否定、疑问句否定、疑问句1.You_buyagift,butyoucanifyouwantto.A.mustB.mustntC.havetoD.donthaveto2.WhenIwasyoung,IwastoldthatI_playwithfire.A.wouldntB.needntC.mustntD.darent3.-MayIsmokehere?-Ifyou_,chooseaseatinthesmokingarea.A.shouldB.couldC.mayD.must情态动词表推测情态动词表推测可能性的强弱层次mustshould/oughttocan/couldmay/might1. That _ be Anns husband, for I am sure that he doesnt wear glasses.A. cant B. may not C. mustnt D. neednt 2. - Good morning. I got an appointment with Miss Smith yesterday. - Ah, you _ be Mr. Peter.A. might B. must C. would D. can3. What do you mean, there are only ten tickets? There _ be twelve.A. should B. would C. will D. shall4. It is usually warm in my hometown in March, but it _ be rather cold sometimes. A. must B. can C. should D. would5. Although this _ sound like a simple task, great care is needed. A. must B. may C. shall D. should32阅读下列学生书面表达常见错误句子并改正：1.Thanks to your help,I can back to school again.2.You will happy when you get a gift.3.You can be taken Bus No.3 to the theatre.4.We should to help each other.5.You can coming a little earlier.6.You must be return the book before the Summer vacation.7.I will waiting for you at the entrance .8.You should bought a small gift when you visit a friend of yours.go backbetakecomewaitbuy33假如你是李华，你的美国朋友Jack四月份即将来中国旅游，写信向你了解你所在城市的天气、食及交通等方面的情况。请你根据提示用用英文给Jack 写一封回信。1.四月天气暖和，四月底有点热，建议他带薄外套、T恤和短裤。2.饮食：有很多中国传统小吃（介绍一两样），如果不习惯中餐，可以去KFC。3.交通：从机场到你所在城市开车大概2个小时。建议他做大巴比较便宜，打出租车很贵。4.希望Jack 能多呆几天，以便你可以带他游览风景名胜。注意：1.可根据情况增加细节以使行文流畅 2.字数100左右。 3.参考词汇： T恤和短裤T-shirt and pants 风景名胜places of interestDear Jack, I am very excited to know that you will come to China for sight-seeing in April.You want to know something about my city,now I am wtiting to tell you in detail._学以致用：根据提示写一篇小短文，注意谓语动词形式。34参考范文：Dear Jack, I am very excited to know that you will come to China for sight-seeing in April.You want to know something about my city,now I am wtiting to tell you in detail. It is warm in my city in April,but it can be a little bit hot at the end of this month.Thus you dont have to bring thick clothes,just some thin coats ,T-shirts and pants.In your letter,you were worried about the traffic.It is very convenient for you to reach my city.There are buses which will take you here in two hours from the airport every thirty minutes.Besides,the price of ticket is reasonanble.You had better not take taxi ,it is too expensive. I hope you can stay here for several days so that I can show you the places of interest in my city.You may experience a very pleasant trip of good view and delicious food.There are many kinds of Chinese traditional food including Jiaozi and Zongzi.If you are not used to these,we can go to the KFC where you can have food you like. I am looking forward to seeing you soon. Yours, Li Hua 35