1、制作：邓华制作：邓华 2018.5.16Modal verbs一、基本概念：一、基本概念：情态动词是表示可能、怀疑、情态动词是表示可能、怀疑、愿望、许诺、猜测等语气的动愿望、许诺、猜测等语气的动词。词。二、二、情态动词的基本用法情态动词的基本用法 情态动词表示说话人的语气和情绪，其情态动词表示说话人的语气和情绪，其本身词义不完整，不能单独作谓语，必须加本身词义不完整，不能单独作谓语，必须加上动词原形一起才能构成谓语。情态动词没上动词原形一起才能构成谓语。情态动词没有人称和数的变化（有人称和数的变化（have to 除外），有些情除外），有些情态动词有过去式。常见的情态动词有态动词有过去式。常见
2、的情态动词有can,could,may,might,must,have to,shall,should,will,would,ought to,need,dare等。等。含情态动词句型基本结构含情态动词句型基本结构陈述句陈述句：主语主语+情态动词情态动词+动词原形动词原形 We should study hard.一般疑问句一般疑问句：情态动词情态动词+主语主语+动词原动词原形形 Can you help me?特殊疑问句：特殊疑问词特殊疑问句：特殊疑问词+情态动词情态动词+主主 语语+动词原形动词原形What should I do?考纲情态动词用法详解考纲情态动词用法详解1、can与与co
3、uld的用法的用法1）.表示能力表示能力(could 指过去曾经的能力指过去曾经的能力)。She can play chess.He could drive before.2).表示客观上或理论是的可能性。表示客观上或理论是的可能性。It can rain heavily here,especially in summer.4).表示推测表示推测“可能可能”(用于疑问句和否定句用于疑问句和否定句)Could you tell me how I can get to the zoo?2.may/might1).表示请求、允许、许可表示请求、允许、许可,might比比may的语气更委婉的语气更委婉
4、.May I use the car?Im afraid not.2).表示推测表示推测“可能可能”,could的可能性比的可能性比can小。小。It might not be Jane.She hasnt dicided to come here yet.3.must 1）.表示表示“必须必须;应该应该”We must finish our homework everyday.2）.表示表示“一定一定”The book must belong to Jim,there is his name on the cover.2）.表示表示“硬要；偏要硬要；偏要”If you must go hom
5、e,at least call your mom.4.will/would1）.表示表示“请求请求;建议建议”,用于疑问句。用于疑问句。would比比will委婉、客气委婉、客气.Will/Would you please open the window?2）.表示意志或意愿表示意志或意愿I will help you.He promised that he would do anything for you.3）.表示习惯表示习惯,will表示现在的习惯表示现在的习惯,意为意为“总总是是;习惯于习惯于”。would表示过去的习惯性动作表示过去的习惯性动作.This kind of thing
6、 will happen.这种事情总是要发生的这种事情总是要发生的He would stay up late when he was young.4）.表示表示“注定会注定会”Fish will die without water.5.shall1).用于第一人称和第三人称的疑问用于第一人称和第三人称的疑问句句,表示征求对方的意见表示征求对方的意见.Shall we go out for a walk?Shall he wait for you at school?2).用于第二人称和三人称的陈述句用于第二人称和三人称的陈述句,表示表示“命令、警告、允诺或威胁命令、警告、允诺或威胁”.You
7、shall receive my money tomorrow.(表示允诺表示允诺)He shall be sorry for his behavior one day,I tell you.(表示警告表示警告)6.should 1)表示劝告和建议,意为“应该”We should help each other.You should be polite to the old.2)表示惊讶、意外表示惊讶、意外,作作“竟然竟然”讲讲To my surprise you should not know about me.3)表示可能性很小表示可能性很小,但并非完全不可能，用于但并非完全不可能，用于i
8、f 引引导的条件状语从句。导的条件状语从句。If he should be free yesterday,he would come to our party.4）表示推测，意为）表示推测，意为“想必一定、照说应想必一定、照说应该、估计该、估计”等。等。He should be free by now.7.ought to1).表示义务表示义务,作作“应当应当”讲讲,语气比语气比should强烈强烈As a student,you ought to study hard.You oughtnt to speak so much.2).表示含蓄或不完全肯定的推测表示含蓄或不完全肯定的推测,意为意
9、为“应该应该”或或“应是应是”He ought to know my telephone number.8.dare.用于疑问句、否定句和条件状语从句中用于疑问句、否定句和条件状语从句中,表示表示“敢敢;敢于敢于”。She darent go alone at night.How dare you come again?Go if you dare.9.need表示表示“需要需要;必要必要”,用于疑问句、否定句和用于疑问句、否定句和条件状语从句。条件状语从句。You neednt worry about me.Need I give you a hand?Need I help you if
10、you get into trouble?容易混淆的情态动词容易混淆的情态动词 用法区别用法区别 can/could/be able tocan/couldcan只有现在式只有现在式和过去式和过去式(could),表示表示一般一般be able to用于多种时态，用于多种时态，was/were able to表示曾表示曾经通过努力而做成某事经通过努力而做成某事 You neednt worry about me.You neednt worry about me.You neednt worry about me.情态动词情态动词主要用法主要用法would/used towould表示过去习惯
11、性或重复性的动作表示过去习惯性或重复性的动作,并并无跟当前对比之意无跟当前对比之意used to强调跟现在对比，表示过去经常发强调跟现在对比，表示过去经常发生的动作或存在的状态生的动作或存在的状态,表明表明“现在现在不再不再以前那样以前那样了了”情态动词后面跟完成时情态动词后面跟完成时情态动词情态动词+have done的用法的用法1.对过去的推测对过去的推测1).must have done表示对过去已经发生的行表示对过去已经发生的行为进行推测为进行推测,意为意为“准是、想必、一定做了某准是、想必、一定做了某事事”,通常用于肯定句。通常用于肯定句。You must have gone swi
12、mming,for your hair is wet now.2).may have done 和和 might have done 也许、也许、或许、已经或许、已经表示对过去所发生动作的推测表示对过去所发生动作的推测,常用于肯定句常用于肯定句或否定句。或否定句。Im not sure.He might have invited you.3).can have done 和和could have done表示对过去所发生动作的怀疑和否定表示对过去所发生动作的怀疑和否定,通通常用于否定句和疑问句常用于否定句和疑问句Where can Tom have gone?I saw Li Lin play
13、ing football just now.He couldnt have been ill.2.表示遗憾、后悔或责备表示遗憾、后悔或责备 1).should have done 和 ought to have done 用于肯定句表示“本该做某事,而实际上没有做”You should have given her a hand just now.用于否定句表示用于否定句表示“本来不该做的事反而本来不该做的事反而做了做了”。You oughtnt to have invited him.2).might have done用于肯定句用于肯定句,表示本应该或可以做某事表示本应该或可以做某事,带有
14、轻微的责备的语气。带有轻微的责备的语气。You might have helped your mother with housework.3).could have done 本来可以本来可以常用于肯定句常用于肯定句,表示过去没有实现的可能表示过去没有实现的可能性。性。You could have passed the exam,but you were too careless.4).neednt have done 用于否定句用于否定句表示过去表示过去“本来不需要本来不需要”You neednt have worried about me.你本不必为我担心。你本不必为我担心。情态动词后面跟
15、进行时情态动词后面跟进行时 情态动词情态动词+be+doing表示表示“想必正在想必正在”，“可能正在可能正在”，“应当正在应当正在”They may be discussing our problem.She cant be telling the truth.They must be chatting on the Internet.You shouldnt be working like this.EXERCISES一、用适当的情态动词填空一、用适当的情态动词填空1.You worry about me.neednt 2.He looks so pale,he be ill.must 3
16、.Plants die without sunshine.will 4.The red coat be Bobs,he doesnt like red at all.cant.5.We learn from each other.6.Miss Li help me when she worked at our school.7.He come to see you again.8.We help parents with housework.should would darent ought to 二、单项选择：1.You fail in the exam without hard worki
17、ng.A.will B.would C.mustnt D.can 2.He had to give up smoking because of his illness,he?A.did B.does C.didnt D.doesnt 3.May I wear jeans to take the party?Sorry,you ,you should wear a suit.A.neednt B.cant C.may not D.mustnt4.Lets take a walk,we?A.can B.would C.must D.shall A C B D 5.I dont know if he
18、 play the guitar before.A.would B.could C.did D.had 6.There goes the bell,Wed better speak.A.not B.not to C.wont D.dont 7.Students tell lies.A.may not B.must C.can D.mustnt 8.We follow the rules here.A.can B.may C.oughtto D.could B A D C 9.You waken me up,its Sunday today.A.neednt have B.must have C.need have D.mustnt have10.I hope that everyone pass the exam.A.can be able to B.will be able to C.would be able to D.are able to11.Dont eat in class._ A.Yes,I wont.B.Sorry,I cant.C.Sorry,I wont.D.OK,I didnt.A B C THE END!THANK YOU!谢谢欣赏
