高中英语语法专题复习课件--情态动词(共22张PPT).ppt

1、1.常用情态动词的用法比较1)在表示“可能性”方面 must,can,should,may,might 都可以用于表示“可能性”。a.must 表示以事实为依据而进行的逻辑上的推理，它所指的动作或状态发生的可能性最大。b.can 和should 表示以事实、理由为依据而进行猜测，它们所指的动作有发生的可能性，但语气没有must 那么肯定。其中，should 的主观性较强。c.may 和might 语气较弱，表示说话人根据自己的主观判断而进行的猜测。其中，might 的语气更弱一些。2)在表示“允诺”方面 can,may,might 都可以表示“允诺”，其中might最为客气、委婉。如：You

2、can watch TV for as long as you like.May I use your phone please?Might I possibly borrow your umbrella please?3)在表示“应该”方面 must,ought to,should 都能用来表示“出于某种职责、义务而应该”的意思。must的语气最强烈，ought to居中，而should是表达这方面意思的普通词。如：You must cut down on smoking.You ought to visit your parents more often.You should try th

3、at new restaurant.2.情态动词的特殊用法1.1)shall 用于第一人称表示坚强的信念和决心；用于第二、三人称，表示许诺、命令或规定等。如:2.We shall not fail.If you really want a dog,you shall have one.She shall not stay under my roof.Candidates shall remain in their seats until all the papers have been collected.2)should表示惊讶等感情,意为“竟然”。如：Its odd you should

4、mention Ben!I was just thinking about him.3)must 表示说话人的不满，意为“偏要,硬要”。如：Eric must come and worry me with questions,just when I am busy cooking the dinner.If you must smoke,please go outside.4)may 表示祝愿;may as well 用来提出建议,意为“还是的好”;may well 用来表示可能性，意为“很可能”。如：May you be happy!You may as well tell us now.W

5、ell find out sooner or later.His appearance has changed so much that you may well not recognize him.3.“情态动词+have done”结构1)could/might/should/ought to/need have done意为“本来能/可能/应该/需要做，但实际上未做”。如：He could have escaped,but he chose to stand and fight.It was an easy test and he should have passed,but he di

6、dnt.2)“情态动词+have done”还可用来表示推测过去可能发生的事情。如：Did you say anything that might have upset her?I.选用括号内合适的内容填空。1.I love the weekend,because I _(neednt,mustnt)get up early on Saturdays and Sundays.(北京2016)2.It was really annoying;I _(couldnt,shouldnt)get access to the data bank you had recommended.(天津2016)n

7、eedntcouldnt3.Cant you stay a little longer?Its getting late.I really _(can,must)go now.My daughter is home alone.(北京2015)4.Life is unpredictable;even the poorest _(shall,might)become the richest.(江西2014)mustmight5.George _(mustnt,cant)have gone too far.His coffee is still warm.(浙江2016)6.I _(neednt,

8、couldnt)have worried before I came to the new school,for my classmates here are very friendly to me.(天津2015)needntcantI.选用方框内合适的情态动词填空(每词限用一次)。can shall may should need1.Is David coming by train?He should,but he _ not.He likes driving his car.2.No reader _ remove a book from the library without the

9、permission of the librarian.shallmay3.The girl _ not be Mary shes in New York.4.That the well-dressed young man _ speak to you like that is quite astonishing.5.Havent you seen the sign“No parking”here?Cars _ not be parked here.mustcanshouldcan shall may should needII.选用括号内合适的内容补全下面短文。We make decisio

10、ns all the time,but we 1._(can,must)never be certain whether we are right or wrong.The work you choose to do 2._(may,should)be suitable for you or not.The person you marry 3._(shall,might)be a perfect match or the worst possible choice.Suppose you have saved money for themightcanmayfuture.You 4._(co

11、uld,must)invest it wisely so that it grows in value or you 5._(could,must)lose a lot in a foolish moment.You think you have a healthy diet,but the food you eat 6._(should,may)actually be very bad for you and 7._(should,might)be the cause ofa terrible illness.Perhaps you travel a lot by plane.All the flights you make are routine,couldcouldmaymightbut one of them 8._(must,could)be your last.Decisions!Decisions!You may ask:9._(can,must)I make decisions?The answer is yes.In most cases,you 10._(cant,neednt)skip this process.mustcouldcant