2019届高考英语一轮复习 第二部分 语法专练 专题四 情态动词和虚拟语气课件 外研版.ppt

1、专题四情态动词和虚拟语气,考向分析针对情态动词,高考主要考查的是can,should,must,may,could等常用情态动词的用法,其中情态动词表推测的用法是考查的重点。而针对虚拟语气的考查,主要涉及虚拟语气在条件状语从句、名词性从句中的用法,其中虚拟语气在条件状语从句中的应用是考查的重点。,考点一 情态动词,本专题考点,考点二虚拟语气,考点清单考点一情态动词一、情态动词的基本用法单句填空1.Samuel, the tallest boy in our class, can easily reach the books on the top shelf.答案can句意:Samuel是我们班

2、里最高的男孩,他可以轻松地够到顶层搁板上的书。考查情态动词。can意为“可以,能够”,表示能力,符合语境。2.My room is a mess, but I neednt clean it before I go out tonight; I can do it in the morning.,语境运用,答案neednt句意:我的房间很乱,但是在今晚外出之前我不必打扫它,我可以早晨打扫。设空处表示“不必”,所以用neednt。3.It was really annoying;I couldnt get access to the data bank you had recommended.,

3、答案couldnt句意:真令人恼火,我不能进入你推荐的数据库。根据It was really annoying可知应用couldnt。单句改错4.Meanwhile, I found out that with more patience I must make my toys last longer.mustcould答案mustcould此处表示因为“我”更有耐心了,所以“我”能使“我”的玩具用更长时间了。must表示“必须”;could表示“能”。,情态动词的五个基本用法1.表能力表示现在的能力:can, am/is/are able to表示将来的能力:will be able to表

4、示过去的能力:could表示过去的能力,不表示是否成功地做了;was/were able to表示过去有能力做而且成功地做了。Im going to Europe on vacation together with John if I can find the money.如果我能找到钱,我将和约翰一起去欧洲度假。,用法精讲,2.表推测肯定句:can表示客观上的可能;may/might/could表示可能;must表示一定;should/ought to表示应该,按说应该。否定句:cant/couldnt表示不可能;may not/might not表示可能不;shouldnt/oughtnt

5、 to表示应该不会。疑问句:can/could表示惊讶、怀疑、不相信的态度。Credit cards provide us with lots of convenience, but they can lead to problems.信用卡给我们提供了许多方便,但也会带来一些问题。Will the book I ordered arrive on time?It should, if there is no traffic jam.我订购的那本书会按时到货吗?如果交通不阻塞的话,应该会。,3.表请求、建议、命令、允许、允诺、禁止、义务、责任请求对方允许时用May/Can/Could I.?提

6、出请求、征求对方意见时用Will/Would you.?或Shall I/he/she/they/we.?should/ought to表示应该,shouldnt/oughtnt to表示不应该。may/can(可以)表示允许、许可。must表示必须,mustnt表示禁止。shall与第二、三人称连用,用于陈述句,表示命令、警告、允诺、威胁;当宣布法律、规定时也常用shall。One of our rules is that every student shall wear the school uniform while at school.我们其中的一项规定是,每个学生在校期间都要穿校服。

7、,4.表必要性must do sth.表示“必须做某事”。neednt/dont have to表示“不必”。You neednt get the machine repaired this week. I wont use it until next month.这周你不必请人修理这台机器,到下个月我才用它呢。5.表意愿、决心will/would可与各种人称连用,表示主语的意愿或决心。通常用于有生命体,但有时也用于无生命体,这时是把无生命体拟人化了。Why hasn?t the cook arrived yet today?She just won?t come for such a low

8、 salary.为什么今天厨师还没来?她只是不愿意为这么低的薪水而来。,二、情态动词的特殊用法单句填空1.It was sad to me that they,so poor themselves, should bring me food.,语境运用,答案should句意:让我难过的是,他们自己那么贫穷,竟然还给我带来食物。本题考查情态动词。情态动词should可以表示说话人惊讶的语气,意为“竟然”。2.I cant thank you too much for all your help to my son while we were away from home. 答案cant句意:我无

9、论怎样感谢你都不为过。Cant与enough,too much等连用表示“再也不为过”。,1.can/could的否定式与比较级连用表示最高级。2.can/could的否定式与enough或too(much)连用表示“再也不为过”。3.must可表示“偏要,硬要”,常用于疑问句或条件状语从句。4.may/might as well表示“最好;不妨”。5.would可表示过去的习惯,与used to相比,前者常表示过去反复的动作,后者常表示过去的状态或习惯现在已不复存在。6.should有时表示说话人对某事感到意外、惊奇,意为“竟然”。,单句改错3.Now that youve got a ch

10、ance, you might so well make full use of it.soas 答案soas句意:既然你得到了这个机会,你最好充分利用它。might as well为常用表达,意为“最好;不妨”,故so改为 as。,用法精讲,三、“情态动词+have done”的用法单句填空1.I should have gone (go)to my cousins birthday party last night,but I was not available.答案have gone句意:我昨天晚上本应该去我表兄的生日聚会,但是没有空。这里表示本应该做而没做的事,故答案是have gon

11、e。2.Harry is feeling uncomfortable and he must have drunk too much at the party last night.答案must句意:Harry感觉不舒服,他肯定在昨晚的聚会上喝多了。根据语境可知,此处是对过去发生事情的肯定推测,故空格处填must。,语境运用,3.Sorry, Mum! I failed the job interview again. Oh, its too bad. You should have made full preparations.答案should句意:对不起,妈妈!这次的求职面试我又失败了。哦

12、,真是太糟糕了。你本应该做好充分准备的。should have done表示本该做某事,而实际上并未做,符合题意,故空格处填should。单句改错4.Jerry did not regret giving the comment but felt that he need have expressed it differently.needcould/should答案needcould/should句意:杰里对发表评论不感到后悔,但是他觉得自己本来可以/本应该用不同的方式表达。根据语境可知,此处为could/should have done sth.,意为“本来可以/本应该做某事”。,“情态动

13、词+have done”用法一览表,用法精讲,考点二虚拟语气一、虚拟语气在条件状语从句中的应用单句填空1.If the new safety system had been put (put) to use, the accident would never have happened.答案had been put句意:如果新的安全系统被投入使用,这起事故就不会发生了。本题考查虚拟语气。根据题干中的主句谓语部分would never have happened可知语境是对过去发生的事进行虚拟,因此if引导的从句谓语部分应为had done。再结合语境,可知用被动语态。,语境运用,2.Do yo

14、u have Bettys phone number?Yes. Otherwise, I wouldnt have been (be) able to reach her yesterday.答案have been句意:你有Betty的电话号码吗?有,否则,昨天我就不能联系到她了。设空处是对过去发生的事进行虚拟,应该用would have done结构,此处要用否定形式。3.I was wearing a seat belt then; if I hadnt been wearing one, I would have been injured(injure). 答案have been inj

15、ured句意:我那时系着安全带呢。如果我没系安全带的话,我可能就受伤了。根据句意可知设空处为与过去事实相反的虚拟语气,其谓语形式为would have done。主语I与injure为被动关系,故需用被动语态,故答案为 have been injured。,单句改错4.If you are me,would you talk to him?arewere,答案arewere根据后面的would可知此处为虚拟语气,表示一种假设,if条件从句中are要改为were。虚拟语气在非真实条件句中的运用,语境运用,使用虚拟条件句时要注意以下几点:1.错综虚拟语气当条件状语从句表示的动作或行为和主句表示的动

16、作或行为发生的时间不一致时,动词的形式要根据它所表示的时间做出相应的调整。If you had just followed my advice,you would be better now.如果你刚才听了我的建议,你现在就好多了。If you had studied hard before,you would be a college student now.如果你以前努力学习的话,你现在就是大学生了。2.if条件状语从句的省略在if引导的虚拟条件状语从句中有had, should, were时,可省略if,把were,had,should提到句首,变为倒装句式。If I were at s

17、chool again,I would study harder.Were I at school again,I would study harder.如果我再次上学的话,我会更加努力地学习。,If you had come earlier,you would have caught the bus.Had you come earlier,you would have caught the bus.如果你来得早些,你就能赶上那辆公共汽车了。If it should rain tomorrow,we would not go climbing.Should it rain tomorrow,

18、we would not go climbing.如果明天下雨的话,我们就不去登山了。注意:若省略的条件状语从句中的谓语动词是否定形式时,不能用动词的缩略形式。如:我们可以说Were it not for the expense,I would go abroad now.但不能说Werent it for the expense,I would go abroad now.3.含蓄虚拟语气有时为了表达的需要,在虚拟语气中并不总是出现if引导的条件从句,而是通过其他手段来代替条件从句。,Without your help,we couldnt have finished the work ahead of time.=But for your help,.=If it had not been for your help,.=Had it not been for your help,.没有你的帮助,我们就不能提前完成这项工作。I was ill that day.Otherwise,I would h