2021版高考英语一轮复习语法训练：情态动词和虚拟语气导学案新人教版 9页

情态动词和虚拟语气 一、情态动词 考点一　情态动词的基本用法 ‎1.can和could的用法 ‎(1)表示“能力”。‎ The man can∕could speak two foreign languages.‎ 那个人能说两门外语。‎ ‎(2)表示推测,一般用于疑问句和否定句。‎ ‎—Can the news be true?‎ ‎——这个消息可能是真实的吗?‎ ‎—It can’t be true.‎ ‎——它不可能是真实的。‎ ‎(3)表示可能性。用于肯定句,常译为“往往会,常常会,有时候可能会”。‎ The weather in Ningbo can be very cold in winter.‎ 宁波的冬天会很冷。‎ ‎(4)表示请示、允许。口语中常用could代替can。could用以委婉地提出请求等,但回答时必须用can。‎ Can I have a rest?我能休息一下吗?‎ Could you please help fill this form?‎ 你能帮助我填下这个表格吗?‎ ‎(5)cannot...too∕enough表示“无论……也不过分”“越……越好”。　‎ You can’t be too careful while driving.‎ 开车时越小心越好。‎ You cannot remember enough English words.‎ 你记的英语单词越多越好。‎ ‎2.may和might的用法 ‎(1)表示许可。might比may的语气更委婉。‎ You may use my bike.‎ - 9 -‎ 你可以用我的自行车。‎ ‎(2)表示推测,意为“可能”。may not表示一种不太确定的语气,意为“可能不”。‎ Some people who don’t like to talk much are not necessarily shy; they may just be quiet people.‎ 言语不多的人未必就是害羞;他们或许就是安静的人。‎ ‎(3)may表示请求时,其否定式常用mustn’t表示“禁止”。　‎ ‎—May I use your car?‎ ‎——我可以用一下你的车吗?‎ ‎—No,you mustn’t.‎ ‎——不行。‎ ‎(委婉拒绝可用:Sorry,but I’m using it now.或You’d better not.)‎ ‎(4)表示祝愿,常用结构为“May+主语+动词原形!”‎ May you be happy every day!‎ 愿你快乐每一天!‎ ‎3.must ‎(1)表示义务,意为“必须”(主观意志)。‎ We must do everything step by step.‎ 我们一切都必须循序渐进地做。‎ ‎ 回答以must开头的问句时,若是否定回答,需要用 needn’t 或 don’t have to。‎ ‎— Must we hand in our exercises today?‎ ‎——我们今天必须交练习吗?‎ ‎—Yes,you must.∕No,you needn’t∕you don’t have to.‎ ‎——是的,必须交。∕不,不必今天交。‎ ‎(2)表示推测,意为“一定,必定”,表达十分肯定的语气,只能用于肯定句中。‎ He must be ill.He looks so pale.‎ 他准是病了。他脸色苍白。‎ ‎(3)表示“非得,偏要”。‎ Must you play the piano in such late a time?‎ - 9 -‎ 你非要在这么晚的时间弹钢琴吗?‎ ‎4.shall和should的用法 ‎(1)shall ‎①用于第二、三人称的陈述句中,表示命令、许诺、警告、强制、威胁等,此外,颁布法律、法规时也用shall。‎ You shall have a new bike for your birthday.‎ 你会得到一辆新自行车作为生日礼物。‎ The new law shall come into effect next month.‎ 新法将于下个月生效。‎ ‎②用于第一、三人称的疑问句中,表示说话人征求对方的意见或向对方请示。‎ Shall the man standing outside have a try?‎ 让站在外边的那个人试试?‎ ‎(2)should ‎①表示义务,常译为“应该”,用于各种人称。‎ Parents should take good care of their babies.‎ 父母应该照顾好他们的孩子。‎ ‎②表示惊讶、意外等,常译为“竟然,居然”。‎ I am surprised that you should speak ill of me.‎ 我很惊讶,你竟然说我坏话。‎ ‎5.will和would的用法 ‎(1)表示意愿,用于各种人称的陈述句中。would常指过去的意愿。‎ If you want to read the book,I’ll give it to you.‎ 如果你想读这本书,我可以给你。‎ ‎(2)表示请求,用于疑问句。would语气较委婉。‎ Will you close the window?‎ 请你关上窗户好吗?‎ ‎(3)表示某种倾向或习惯性动作,常译为“总是,习惯于”。would可表示过去反复发生的动作或某种倾向,后面接表示动作的动词,不能接表示状态的词。‎ Every morning he will have a walk along the river.‎ 每天早晨,他总是沿着小河散步。‎ - 9 -‎ ‎ used to表示过去的习惯动作或状态,强调现在已不存在。‎ The old woman would sit in front of the door,watching the people go by.‎ 那个老太太总是坐在门前,看着人们走过。‎ It used to be a factory,but now it is a big supermarket.‎ 它过去曾经是一个工厂,但是,现在它已经是一个很大的超市了。‎ ‎6.need和dare的用法 need和dare既可用作情态动词,也可用作实义动词。用作情态动词时,主要用于否定句和疑问句。‎ ‎—Need I come?‎ ‎——我需要来吗?‎ ‎—Yes,you must.‎ ‎——是的,你必须来。‎ You needn’t telephone him now.‎ 你现在不必打电话给他。‎ She dare not go out alone at night.‎ 她晚上不敢一个人出去。‎ 考点二　“情态动词+have done”的用法 ‎1.对过去发生的事情或状态进行推测 must have done ‎(过去)一定……;语气比较肯定;用于肯定句 may(might) ‎ have done ‎(过去)可能……;语气不确定;用于肯定句和否定句 can(could) ‎ have done ‎(过去)可能……,用于否定句和疑问句,表示怀疑或不确定 Since nobody gave him any help,he must have done the research on his own.‎ 既然没有人帮助他,他一定是独自做的研究。‎ Could he have left the work unfinished?‎ 他会丢下工作不干了?‎ ‎2.表示“与过去事实相反”‎ could have done 过去本可以做某事但实际上没做 - 9 -‎ needn’t have done 过去本不必做某事但实际上做了 ought to∕should have done 过去本应该做某事但实际上没做 oughtn’t to∕shouldn’t ‎ have done 过去本不应该做某事但实际上做了 would have done 过去本来想做某事而没做 would not have done 过去本不愿意做某事而做了 I could have done better in the last exam.‎ 上次考试我本应该考得更好。‎ You needn’t have watered the flowers because it would rain soon.‎ 你本不必浇花的,因为很快会下雨的。(已经浇了)‎ I would have helped you but I was busy at that time.‎ 我本来想帮你可是当时很忙。(没有帮)‎ 二、虚拟语气 ‎1.非真实条件句中虚拟语气的用法 说明 if条件句谓语 主句谓语 与现在事实相反 动词的过去式(be的过去式用 were)‎ would∕should∕could∕might+动词原形 与过去事实相反 had+过去分词 would∕should∕could∕might+have+过去分词 与将来事实相反 动词的过去式(be的过去式通常用were),should do,were to+动词原形 would∕should∕could∕might+动词原形 If I were you,I would go with him.‎ 如果我是你,我就和他一起去。‎ If you had studied harder last term,you could have passed the exam.‎ 如果上学期你学习更努力的话,你考试就会及格了。‎ If it snowed tomorrow,we would take photos.‎ 如果明天下雪,我们就照相。‎ - 9 -‎ ‎ 条件句中有were,had或should时,如果省略if,则需把were,had或should放在主语前,构成倒装结构。如:‎ If I were in your position,I would do the same.‎ ‎→Were I in your position,I would do the same.‎ 假如我处在你的位置,我也会这样干的。‎ 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,你就会赶上公共汽车了。‎ If it should rain tomorrow,we would not go climbing.‎ ‎→Should it rain tomorrow,we would not go climbing.‎ 如果明天下雨的话,我们就不去爬山了。‎ ‎2.错综时间虚拟条件句 当从句谓语动词与主句谓语动词所发生的时间不一致时,它们的形式要根据各自所表示的时间作出相应的调整。‎ If you had worked hard,you would pass the exam this time.(从句指过去,主句指现在)‎ 如果你之前努力学习的话,你就会通过这次考试了。‎ ‎3.含蓄虚拟语气 有时,假设的情况并不用条件从句表达,而是暗含在上下文中,由otherwise,but,or,without,but for 等组成的词组来表达。‎ But for your help,we couldn’t have succeeded.(介词短语)　‎ 要不是你的帮助,我们是不会成功的。‎ Without electricity,life would be quite different today.(介词)‎ 如果没有电,今天的生活就会完全不同。‎ I was ill that day.Otherwise,I would have taken part in the sports meeting.(副词)‎ 我那天病了。否则,我就参加运动会了。‎ He telephoned to inform me of your birthday,or I would have known nothing about it.(连词)‎ 他打电话通知了我你的生日,否则,我对此一无所知。‎ ‎4.某些从句中虚拟语气的用法 ‎(1)用于表示建议、愿望、命令等动词后的宾语从句中。‎ - 9 -‎ 常见的动词有:demand,order,require,insist,suggest,advise,request,urge,command,recommend等。宾语从句中的虚拟语气结构为“should+动词原形”,should 可以省略。‎ ‎[记忆口诀]‎ 一主张:insist 二命令:order,command 三建议:suggest,advise,recommend 四要求:request,require,ask,demand 外加一个敦促:urge The school recommends parents not permit their children to swim in rivers or lakes during summer holidays.‎ 学校建议父母们在暑假期间不要让自己的小孩在河里或湖里游泳。‎ ‎ 当suggest作“暗示,表明”,insist作“坚持认为,坚持说”讲时,从句要用陈述语气。‎ The expression on his face suggested that he was very angry.他脸上的表情表明他很生气。‎ He insisted (that) he heard someone in the next room.他坚持说他听到隔壁屋里有人。‎ ‎(2)wish后跟宾语从句时用虚拟语气。‎ 对现在情况的假设:wish+主语+动词过去式(be动词用were)‎ 对过去情况的假设:wish+主语+had+过去分词 对将来情况的假设:wish+主语+would∕could∕might+动词原形 I wish (that) I were a bird and could fly freely in the sky.我希望我是只小鸟,能在天空自由飞翔。‎ How I wish I had listened to my parents’ advice!‎ 我多么希望我听了父母的建议!‎ I wish I could fly to the moon some day.‎ 如果有一天我能飞到月球上就好了。‎ ‎(3)在“It is necessary∕important∕strange∕natural∕essential+that从句”中,谓语动词常用“ should+动词原形”,should 可以省略。‎ It is important that every member (should) know these rules.重要的是每个成员都应该知道这些规则。‎ It is necessary that students (should) respect - 9 -‎ ‎ teachers.学生应该尊重老师,这是必须的。‎ ‎(4)would rather后跟从句时用虚拟语气,表示愿望,意为“宁愿;但愿”。‎ George is going to talk about the geography of his country,but I’d rather he focused more on its culture.乔治打算谈论他国家的地理,而我宁愿他更多地关注他国家的文化。‎ ‎(5)在“It is (about∕high) time+that 从句”中,谓语动词常用过去式或“should+动词原形(其中should不能省略)”。此句型意为“(现在)该……”,用来表示建议。‎ It is time that you went to school.你该去上学了。‎ It is (high) time that we should start out.‎ 我们(早)该出发了。‎ ‎(6)if only引导的感叹句中,用虚拟语气表示愿望。‎ Look at the trouble we’re in.If only we had taken our teacher’s advice!瞧瞧我们所处的困境,要是我们采纳了老师的建议就好了!‎ ‎(7)as if,as though 引导的表语从句和方式状语从句中常用虚拟语气,与现在事实相反用一般过去时(be动词用were);与过去事实相反用过去完成时;与将来事实相反,用would∕could∕might+动词原形。‎ It seems as though it were spring already.‎ 看起来好像已经是春天了。(事实上不是)‎ The girl is giving us a vivid description of the moon.It seems as if she had been to the moon many times.‎ 这个女孩对月球的描述非常逼真,就好像她去过月球很多次似的。(事实上并没去过)‎ He opens his mouth as if he would say something.‎ 他张开嘴巴,好像要说什么。‎ ‎1.The workers were not better organized,otherwise they 　　　　 (accomplish) the task in half the time.(2019天津) ‎ ‎2.What a pity!You missed the sightseeing,or we 　　　　(have) a good time together.(2019江苏) ‎ ‎3.If he 　　　　 (react)quickly,there could have been a terrible accident.(2017年11月浙江) ‎ - 9 -‎ ‎4.Samuel,the tallest boy in our class,　　　　 easily reach the books on the top shelf.(2017北京) ‎ ‎5.My room is a mess,but I 　　　　 clean it before I go out tonight.I can do it in the morning.(2017天津) ‎ 答案及剖析:‎ ‎1.would have accomplished　考查虚拟语气。句意:工人们没有被更好地组织,否则他们会用一半的时间完成任务。此处表示与过去事实相反的假设,用would have done sth.表示“本来能够做某事”。‎ ‎2.would have had　考查虚拟语气。句意:真遗憾!你错过了观光,否则我们在一起会玩得很开心。根据What a pity!You missed...以及or(否则)可知,此处是与过去事实相反的虚拟语气,故用would have done结构。‎ ‎3.hadn’t reacted　考查虚拟语气,此处的语境是“如果不是他快速采取行动,那么将会有一场严重的交通事故”。讲述的是过去发生的事情,在条件从句中应该用hadn’t done。‎ ‎4.can　本题考查情态动词。本句的句意:塞缪尔是我们班里最高的男孩,他可以轻松地够到书架顶层的书。根据语义可知应用情态动词can“可以,能够”表示能力。‎ ‎5.needn’t　本题考查情态动词。句意:我的房间很乱,但是在今晚外出之前我不需要打扫它,我可以在(明天)早晨打扫。根据语境可知,我不需要打扫或没必要打扫房间,用needn’t符合题意。‎ - 9 -‎