《助动词和情态动词》PPT课件.ppt
助动词,助动词本身没有实际意义,不能独立构成谓语,可表示时态、语态或构成否定及疑问形式。常见的助动词有:be,have,do,will,shall,be类助动词,1)be类助动词有哪些?am,is,are,was,were,been 2)请按时态或语态把上面的词分类。1.一般现在时:2.一般过去时:3.完成时态:4.被动语态:,am,is,are,was,were,been,All of them.,3)含有be类助动词的句子该如何变否定句?They were watching TV when we got there.They watching TV when we got there.4)一般疑问该如何变?We are doing our lessons now.Are you doing your lessons now.,werent,have类助动词,1)have类助动词有哪些?have,has,had,having2)have类助动词与过去分词构成完成时。My uncle has come back home.Before we went home,we had had a little rest.Having done the work,we had a bath.,will类助动词,1)will 类助动词有哪些?will,would,shall,should 2)这类动词后加_,构成将来时态。There will be more trees in one hundred years.3)注意:shall 仅用于第一人称。I shall be fifteen years old next birthday.,动词原形,do类助动词,1)这类助动词有哪些?do,does,did 2)这类动词与行为动词一起构成否定句和疑问句。Do you enjoy living in China?Does your sister like playing basketall?He didnt watch TV last night.,情 态 动 词,1.请回忆你所学过的情态动词。can/could,may/might,must,have to,need,shall/should,will/would2.你知道他们是什么意思吗?can表_,may _ must _推测有把握 should _,would _,have to _表客观,能力,许可,必须,应该,愿,被迫,这么多情态动词,你知道这么用吗?,can,could 的用法 can在以下句子中分别是什么用法?意思?1)Can you play basketball?2)Li Hua cant be in the classroom.3)You can go now.,表能力,意为“能,会”,表示怀疑,猜测,常用于否定句和疑问句中,表示许可,意为“可以”(相当于may),4)Can I play with the toy now,Mum?2.could是can的过去式,可以表示过去的能力。I could swim when I was seven.3.以can开头的一般疑问句,其肯定和否定回答分别是can和cant;以could开头的一般疑问句,其肯定和否定回答分别是could和couldnt.,表示建议、请求(常用于疑问句),may,might 的用法1.may在以下句子中分别是什么用法?意思?1)He may come tomorrow.表示推测,意为“可能;也许”,用于肯定句2)You may go now.表示许可,3)May I borrow your book?表示请求、许可,意为“可以”。-May I go now?-_.(注意:may表示请求时,用于主语为第一人称的一半疑问句,其否定回答用mustnt或cant,表示“不可以,不许,禁止,阻止”),No,you mustnt/cant.,must的用法1)We must love our country.表示“必须,应该”2)The man must be a doctor.表示很有把握的推断,“一定”3)must表示推测时一般用于肯定句;在疑问句和否定句中一般应用can,否定句中也可以用may,但may not表示“可能不”,而cant表示“不可能”。,4)否定句中,mustnt表示禁止,意为“不允许”。以must开头的疑问句,肯定回答应用must,而否定回答则常用neednt和dont have to(不需要,不必)eg:Theres someone knocking at the door.It must be Jim.-Must I finish the project today?-No,you neednt/dont have to.,need的用法You neednt come next time.表示需要、必须(主要用于否定句和疑问句)2)Need I go to bed now?Yes,you must.No,you neednt.,shall 和should 的用法You shall have your book soon.表示许诺、警告、命令(用于陈述句的第二、三人称)2)Shall he come to see you?Shall we go out for a walk?征求对方意见或请求(用于第一、三人称的问句)3)Shall I tell John about it?-No,you neednt.I told hime just now.,will 和 would的用法Ill help you if I am free this afternoon.表示意愿、意志(用于多种人称)2)Fish will die out of water.总是、惯于(习惯性动作或状态)注意could,should,would,might等过去式有时并不表示过去,而是表示一种更委婉客气的语气。Would you like some bananas?,情态动词用法大串联?考考你,准备好了吗?,Q1:must与have to 都有“必须”的意思,其区别是什么?must表示主观看法;have to表示客观需求“不得不”Q2:must也可表示很有把握的猜测。那表示推测的情态动词还有那些?与must的区别有哪些?can may might could,1)can表推测,只用于否定句和疑问句中,must表肯定推测,cant表否定推测。2)may,might,could表示可能。Q3:当must意为“应当”时,和should(应该)有什么区别?We must love our country.You should see a doctor.(must表示主观的看法;should表示建议),Q4:must是“必须,应当”的意思,那么mustnt如何理解呢?你知道neednt,cant 与shouldnt,may not分别是什么意思吗?mustnt:不允许 neednt:不需要,不必 cant:不可能 shouldnt:不应该 may not:可能不(小提示:这几个词的意思一定要记住并区分,因为考试时经常出现),Q5:以must开头的疑问句的否定回答用什么?neednt或dont have to 那么以may,need开头的一般疑问句用什么来回答呢?may的否定回答用:mustnt或cant;need的肯定回答用:must 否定回答用:neednt,1.-_ you turn down your radio,please?-Yes,I can.A.May B.Need C.Must D.Can2.What will the weather be like tomorrow?-It _ be rainy,cloudy or sunny.Who knows?A.must B.might C.shall D.shouldnt3.How was the youth club last night,Mark?-It was great fun.You _ come.A.must B.can C.should D.may4.This history book _be Bobs sisters.His sister is only a baby.A.must B.might C.cant,D,B,C,C,5.Dont put off todays work for tomorrow.I mean,todays work _today.A.may do B.must do C.may be done D.must be done6.You _ jump onto a bus while it is moving.Its too dangerous.A.may not B.mustnt C.may D.must7.How is our friend coming?-Im not sure.He _ drive here.A.may B.can C.must D.will,D,B,A,8.Will you go to the museum with me?-Sorry,_.My aunt is coming to see me.A.I dont B.I cant C.I neednt D.I mustnt9.-_ I use your mobile phone?-Certainly.Here you are.A.May B.Must C.Should D.Need10.Shall I tell John about it?-No,you _.I told him just now.A.neednt B.cant C.mustntD.shouldnt,B,A,A,11.Look!The man at the ate _ be our headmaster.He is always standing there every morning.-No,it _ be him.He is holding a meeting in the office now.A.must;cant B.must;mustntC.cant;cant D.cant;mustnt12.-_ the exam paper be handed in right now?-No,it doesnt have to.You may hand it in before 11:30.A.Can B.Must C.Should D.May,A,B,13.Mr.White is of great help,so you _ let him go.A.had not better B.had better dont C.had better not D.had no better14.Will you answer the telephone?It _ be your mother.-Sorry.I _.Im very busy.A.can;mustnt B.will;cant C.may;cant D.need;will,C,C,15.May I take my pet dog with me into the cinema?-The rule says no.So you _.A.can B.mustnt C.may D.neednt16.Our classroom must clean every day.Keep B.to keep C.be kept D.to be kept17.Lisa,_ you speak English?-Yes,but only a little.A.need B.must C.may D.can,B,C,D,1.could 2.mustnt 3.might/may 4.should 5.was able to 6.should 7.have to 8.Would 9.May;can 10.shouldnt 11.must;cant 12.must 13.neednt 14.may 15.Will,