20．[2010·湖南卷]
You ________ buy a gift，but you can if you want to.
A．must
B．mustn't
C．have to
D．don't have to
【解析】 D 考查情态动词。
don’t have to意为“没有必要”，符合语境。
句意为：你没有必要买礼物，但如果你想买的话，你也可以买。
专题八 │ 实战演练 21．[2010·陕西卷]
— May I take this book out of the reading room?
— No，you________. You read it in here.
A．mightn't
B．won't
C．needn't
D．mustn't
【解析】 D 本题考查情态动词的用法。表示“禁止；千万别做某事”时，要用mustn't。 22．[2010·江西卷]
I have told you the truth. ________ I keep repeating it?
A．Must
B．Can
C．May
D．Will
【解析】 A 考查情态动词的用法。must在此意为“必须……吗？非得……吗？” ,句意为：前半句说我告诉你事实了, 这里用的是现在完成时, 表示过去的动作对现在造成了影响, 既然我已经说了, 我还必须重复一遍吗？ 专题八 │ 实战演练 23．[2010·江苏卷]
—
I haven’t got the reference book yet， but I'll have a test on the subject next month.
—
Don’t worry. You ________have it by Friday.
A．could
B．shall
C．must
D．may
【解析】 B 本题考查情态动词。
当主语为第二、三人称时，情态动词shall表示说话人给对方命令、警告、允诺或威胁，本句表示允诺。 专题八 │ 实战演练 24．[2010·江苏卷]
George is going to talk about the geography of his country，but I'd rather he ________ more on its culture.
A．focus
B．focused
C．would focus
D．had focused
【解析】 B 本题考查虚拟语气。
would rather＋从句，从句表示对现在或将来虚拟时应使用一般过去时。 专题八 │ 实战演练 25．[2010·全国卷Ⅰ]
Just be patient. You ________ expect the world to change so soon.
A．can't
B．needn't
C．may not
D．will not
【解析】 A 考查情态动词的用法。
句意：耐心一点儿, 你不能期望世界变化如此快。通过选项此题考查情态动词, can’t在否定句中可以表示推测, 译为不可能,可以表示能力, 译为不能够,语气强烈。也可以表示命令, 不允许, 但是语气比mustn’t弱, 具有劝慰的意思, 根据句意此题中选择A, can’t表示劝慰。 专题八 │ 实战演练 26．[2010·福建卷] Teachers recommend parents ________ their children under 12 to ride bicycles to school for safety.
A．not allow
B．do not allow
C．mustn't allow
D．couldn't allow
【解析】 A 考查虚拟语气。句意为：教师们建议：为了孩子们的安全，父母不应让12岁以下的孩子骑自行车去学校。recommend意为“建议”，其后接的宾语从句采用虚拟语气，从句谓语动词用“should＋动词原形”的形式，should可以省略。 专题八 │ 实战演练 27．[2010·天津卷] Mark ________ have hurried. After driving at top speed，he arrived half an hour early.
A．needn't
B．wouldn't
C．mustn't
D．couldn't
【解析】 A needn't have done 本没有必要做某事，实际上做了。句意：迈克本来不必要那么忙的。这么高速驾驶之后, 他早半个小时到达了。根据后面的语境, 提前半个小时到达, 说明Mark本来不必那么匆忙, 所以用needn’t
have done 结构, 表示 “本来不必要做某事的而实际上做了”。 专题八 │ 实战演练 28．[2010·重庆卷] You ________ park here! It's an emergency exit.
A．wouldn't
B．needn't
C．couldn't
D．mustn't
【解析】 D 考查情态动词词义辨析。由句意“这里是紧急出口”，可知此处不允许停车，所以用mustn't表示“禁止，不许”。 专题八 │ 实战演练 29．[2010·北京卷] —Good morning. I've got an appointment with Miss Smith in the Personnel Department.
—Ah，good morning. You ________be Mrs. Peters.
A．might
B．must
C．would
D．can
【解析】 B 本题考查情态动词在语境中的运用。 第一个说话人说和史密斯小姐有约, 那下面的人就回应说, "那您一定就是Mrs. Peters了“,用must来表示肯定推测。 30．[2010·山东卷]
I ____________ have watched that movie — it'll give me horrible dreams.
A．shouldn't
B．needn't
C．couldn't
D．mustn't
【解析】 A shouldn't have done意为“本不应该做但实际已经做了(表达后悔的情绪)” . e.g. You should have invited me to your wedding, but you forgot. 专题八 │ 实战演练 如：If he were to come, I would join him in the discussion. ＝ Were he to come, I would join him in the discussion. 如果他来，我将和他一道参加讨论。 (5) 有些虚拟条件句没有从句，虚拟条件句是通过上下文或介词短语表示出来的。如：
But for air and water, there would be no life on the earth. 要是没有空气和水，地球上就没有生命。(介词短语but for提供了虚拟条件)
With your help, we might finish the plan earlier. 要是有你的帮助，我们就可以早些完成任务。(介词短语with your help充当虚拟条件句) 专题八 │ 正面解读 2． 虚拟语气在wish从句中的用法 专题八 │ 正面解读 宾语从句 愿望 I wish 主语＋动词过去式 现在不能实现的愿望 主语＋had＋过去分词 过去不能实现的愿望 主语＋would/might＋动词原形 将来不能实现的愿望
I wish I were a doctor. 我希望我是个医生就好了。(现在)
I wish that the rain would stop. 我希望雨能停下来。(将来)
I wish that he had not made so much fuss about it.
我希望他不要把事情搞大了。(过去) 3． 虚拟语气在名词性从句中的使用 (1) 在insist；command，order；demand，request，require，desire；advise, propose, suggest，recommend 等表示“命令、要求、建议”的动词后接的宾语从句中要使用虚拟语气。如：
He suggests that she (should) leave the house at once.
他要她立刻离开这所房子。 专题八 │ 正面解读
He proposed that we (should) deal with the problem by the view of development.
他建议我们应该用发展的眼光处理这个问题。 (2) 与上述动词相对应的名词suggestion, order, demand , proposal 等后的表语从句、同位语从句中也要使用虚拟语气(should可省略)。如：
My proposal is that we (should) set a deadline for handing in the plan.
我的建议是为这个计划设定一个上交的期限。 专题八 │ 正面解读 (3) 在It be suggested (ordered, demanded, proposed, … )that… 结构中，主语从句中也要使用虚拟语气。如：
It's required that every student be on time for school.
要求每个学生准时到校。 (4) 在do you suggest/recommend用在特殊疑问句中作插入语时，句子的动词也使用虚拟语气，即“should＋动词原形”的形式，其中should可以省略。如：
What type of computer do you recommend/ suggest we (should) buy?
你建议我们买什么类型的电脑呢？ 专题八 │ 正面解读 (5) 在It's＋necessary，essential，important, strange, natural等形容词＋ that从句或It's a pity，a shame等名词＋ that 从句中，谓语动词可以使用should do。如：
It is necessary that the badly wounded man should be treated immediately. 这位重伤员必须马上治疗。
It's a pity that you should be so careless.
你竟然如此粗心，真是可惜。 专题八 │ 正面解读 4． 虚拟语气在状语从句中的用法
在as if/though引导的状语从句中，谓语动词用过去式表示与现在相反的情况；用过去完成式，表示与过去相反的情况等。其变化与wish后的宾语从句的变化相同。如：
I've loved you as if you were my relative.
我一直爱你仿佛你是我的亲人。 5． 虚拟语气在其他一些句型中的用法 (1) It's high/above time (that)从句中，谓语动词可以使用过去式，也可使用should＋动词原形；表示“早该……了”，其中should不可省略。如：
It's high/above time we got up/should get up. 我们早该起床了。 专题八 │ 正面解读 (2) would rather＋从句中，谓语动词用过去式表示与现在或将来的情况相反；用过去完成式，表示与过去的情况相反。如：
I would rather you came tomorrow. 我宁愿你明天来。 (3) if only…要是……多好啊。如：
If only you hadn't offended him. 你当时不惹他就好了。
If only he could come tomorrow. 他明天能来就好了。 (4) 其他一些表示祝愿的句型。如：
May you succeed！祝你成功！
Long live the People's Republic of China.
中华人民共和国万岁！
专题八 │ 正面解读 1.
【误】 The streets are all dry; it mustn't have rained last night.
【正】 The streets are all dry; it can't have rained last night.
【解析】 对某一事实的否定推测不能用must，而要用can't 或couldn't表示“不可能”。 专题八 │ 反面解读 反面解读 2． 【误】 I didn't see Mary at the meeting yesterday. She might be ill, I guess.
【正】 I didn't see Mary at the meeting yesterday. She might have been ill, I guess.
【解析】 猜的事情发生在昨天，因此要用情态动词＋have done形式，当动词是be时，很容易忽略它的时态意义，要特别留意。 3． 【误】 He must be very friendly at times.
【正】 He can be very friendly at times.
【解析】 句意为：他有时会很友好。可知此处并非对现在的状态进行推测，而是一种理论上的可能性，因此用can。 专题八 │ 反面解读 4． 【误】 I can't find my keys. I may/might forget them on the playground yesterday.
【正】 I can't find my keys. I may/might have left them on the playground yesterday.
【解析】 表示对过去情况的推测，通常用must/may/might have done sth. 另外，表示“把……忘记在某地”应用动词leave。 专题八 │ 反面解读 5． 【误】 The fire spread through the hotel quickly, but everyone could get out.
【正】 The fire spread through the hotel quickly, but everyone was able to get out.
【解析】 表示在过去成功地做到了某事，肯定句中通常用was/were able to do sth.。 专题八 │ 反面解读 6． 【误】 Will I open the window for you?
【正】 Shall I open the window for you?
【解析】 shall与第一、第三人称连用，表示征求意见或请求指示，这时不可用will。will通常与第二人称连用，即Will you…？ 7． 【误】 The plant is dead. Maybe I should give more water.
【正】 The plant is dead. Maybe I should have given more water.
【解析】 根据第一句可知，植物已经死亡，所以应该是自责：本应该多浇些水的。要用should have done形式表示“本应该做……而未做”。 专题八 │ 反面解读 8． 【误】 Hadn't they saved us, we would have been drowned in the stormy river.
【正】 Had they not saved us, we would have been drowned in the stormy river.
【正】 If they had not saved us, we would have been drowned in the stormy river.
【解析】 当条件中含有were, had, should等时，可省略if，从而把were, had, should提到主语之前。若条件句为否定句，则只把were, had, should提前，not仍放在主语之后。 专题八 │ 反面解读 9． 【误】 If only I saw the film yesterday.
【正】 If only I had seen the film yesterday.
【解析】 if only后句子若表示过去的一种愿望，其谓语动词应用过去完成式，即if only sb. had done sth. 。
专题八 │ 反面解读 1． — Everyone in my class passed the exam.
— Oh，really？It ________ difficult.
A．can't have been
B．needn't have been
C．must be
D．mightn't be
【解析】 A 考查情态动词。
表示否定的推测应使用 can‘t /cannot。
对过去进行推测，表示“一定不”应使用 can‘t have done。
句意为： “我们班上每个人都通过了考试。”
“哦，真的吗？那题目一定不难。” 专题八 │ 实战演练 实战演练 2． [2009·安徽卷]
Some people who don't like to talk much are not necessarily shy；they ________ just be quiet people.
A．must
B．may
C．should
D．would
【解析】 B
句意为：有些人不喜欢讲话不一定是害羞，他们可能是安静的人。此处用may表示“可能”之意。 专题八 │ 实战演练 3． — Why didn't you answer the phone last night?
— I ________ when you called.
A．had to have slept
B．had to be sleeping
C．must have been sleeping
D．must have slept
【解析】 C 由时间状语和结合语境来看，这是对过去某个时间点正在发生事情的肯定推测，再结合题意，应该是must have been doing结构，选C。
专题八 │ 实战演练 4． When I lived with my roommates in the university, we ________ often talk into the night.
A．might
B．must
C．should
D．would
【解析】 D 这里描述的是过去经常发生的动作(或过去经常做的事情)。
e.g.
After dinner, he would sit around Grandpa, listening to his stories. 专题八 │ 实战演练 5． — This is the first time I ________ my first picture with my own hands.
— It is time that you ________ a picture for me.
A．took; took
B．have taken; took
C．took; will take
D．will take; have taken
【解析】 B
This/It is the first time that…中，从句的谓语动词通常用现在完成式；
It's (high) time that…中，从句谓语动词通常用一般过去式(即虚拟语气)，意为“该是做……的时候了”。 专题八 │ 实战演练 6． —Why hasn't Jack come back yet？________anything have happened to him?
—I'm not sure, but I guess something ________.
A．May；must have
B．Can；may have
C．Must；may
D．Dare；might have
【解析】 B 考查情态动词。在一般疑问句或特殊疑问句中表推测时常用can或could，推测发生过的事情时情态动词后要接完成式，只能选B。 专题八 │ 实战演练 7．It is usually warm in my hometown in March, but it________ be rather cold sometimes.
A．must
B．can
C．should
D．would
【解析】 B
can用在肯定句中可以指“有时会，可能会”，表示客观情况或逻辑上的可能性。句意为：三月份在我们家乡通常比较暖和，但有时也会非常冷。 8． Liza________ well not want to go on the trip — she hates traveling.
A．will
B．can
C．must
D．may
【解析】 D may well (not) do sth.意为“很可能(不)干某事，完全(没)有可能干某事”。 专题八 │ 实战演练 9． Look at the floor, Tom！________you watch TV while having a meal?
A．Should
B．Could
C．Would
D．Must
【解析】 D
Must 表示与说话人愿望相反或不耐烦“非得、偏要”。
如：
Must you make so much noise？你就非得弄出这么大声吗？ 专题八 │ 实战演练 10．The soccer team has been doing well this season，so they
________ win the championship.
A．should
B．might
C．would
D．must
【解析】 A 本题考查情态动词。
句意为：这个足球队在这个季度训练得很好，因此，他们应该会赢得冠军。
根据常理进行推测表示“应该……”时用should。 专题八 │ 实战演练 11．When the ship sailed out from Thailand, the 16 sailors on board ______ that only half of them would return again.
A．will never think
B．can never think
C．needn't have thought
D．couldn't have thought
【解析】 D 考查“情态动词＋完成式”的用法。
根据句意“当这艘轮船从泰国驶出的时候，船上的16名船员不会想到他们当中只有一半的人会返回”可知，这里表示对过去事情的否定推测，选D。 专题八 │ 实战演练 12．—
What does the sign over there read?
— No person ______________ smoke or carry a lighted cigarette in this area.
A．will
B．shall
C．may
D．must
【解析】 B 考查情态动词的特殊用法。
答句句意为：任何人在这里都不能吸烟或者是携带点燃的香烟。
Shall在这里表示强制， 用于法令、条约、规章中，意为“必须，应该”。 专题八 │ 实战演练 13．It‘s hard to believe that such a greedy man________ donate so much to the Project Hope.
A．may
B．need
C．can
D．shall
【解析】 C 考查情态动词的特殊用法。
句意为：这么贪婪的人竟能为希望工程捐出这么多钱，真是难以置信！
Can在这里表示惊讶、不相信，意为“居然会，竟能”。
How can you be so careless!
Should也可以表示说话人的感情色彩，如惊奇、愤怒、失望等，意为“竟然” 。E.g.
I’m surprised they should refuse our invitation. 专题八 │ 实战演练 14．For environmental reasons，we ________ as well take these waste products and have them recycled.
A．should
B．would
C．might
D．could
【解析】 C 考查情态动词。 所填词与as well构成固定搭配，意思是“不妨…… ，还是 ……为好”用may/might，选C。E.g. It’s too late. You might as well not go. 15．We ________ here at lunch time; we were delayed at the airport, though.
A．could be
B．should be
C．must have been
D．would have been
【解析】 D would have done sth.表示与已经发生的事实相反，意思是“本来会……但实际没有”。句意为：我们本来能在午餐时到达，但我们在机场被延误了。 专题八 │ 实战演练 16．— Jenny took the 8：00 bus to Guangzhou this morning.
— Really？He ____________________ the 9：00 train.
It's much more comfortable and safer to travel by train.
A．could have taken
B．should take
C．must have taken
D．can take
【解析】 A 考查情态动词的用法。
上句表示珍妮已乘坐8点的汽车去了广州。答句句意为：她本可以坐9点的火车去的，坐火车舒服得多，安全得多。
“情态动词could＋完成式”表示“本来可以，而实际上并没有那么做”。 专题八 │ 实战演练 17．[2010·四川卷]
— ________ I take the book out?
— I'm afraid not.
A．Will
B．May
C．Must
D．Need
【解析】 B 考查情态动词词义辨析。
表请求可用情态动词can, may, could, might ,表允许用can/may,用于一般疑问句，表示请求。
句意为： “我可以将这本书带出去吗？” “恐怕不行”。故应选表请求的情态动词may。正确答案为B。
专题八 │ 实战演练 18．[2010·安徽卷]
Jack described his father，who ________ a brave boy many years ago，as a strong-willed man.
A．would be
B．would have been
C．must be
D．must have been
【解析】 D 考查情态动词。
句意为：杰克把他父亲描写成一个有坚强意志的人，他很多年前就一定是一个勇敢的男孩。
根据many years ago可知，是对过去事情的推测。would have been多用于条件句的虚拟语气中。 专题八 │ 实战演练 19．[2010·浙江卷]
Had I known about this computer program，
a huge amount of time and energy ________.
A．would have been saved
B．had been saved
C．will be saved
D．was saved
【解析】 A 本题考查虚拟语气。根据Had I known提示，可知此句是虚拟语气，且与过去事实相反，故主句谓语用would have done的形式。此外本句还是被动，选A。 专题八 │ 实战演练 专题八
正反解读 情态动词和虚拟语气
热身导入 Can you list some modal verbs that you remembered?
modal verbs can/could may/might will/would shall/should must ought to Used to dare be able to need have to 专题八 │ 考点荟萃 情态动词的语法特征 1情态动词除ought to和used to外，后面只能接不带to的不定式。 2情态动词没有人称，数的变化，will can dare 除外。 3情态动词“时态”的形式并不是区分时间的主要标准。 自主学习 专题八 │ 考点荟萃
情态动词主要用来表示说话人的情感、态度等，是中学英语语法的重点，也是高考的热点，是单项填空必考的一个知识点。情态动词在近五年高考中主要考查四点：情态动词表示推测和可能性的用法；情态动词与虚拟语气；情态动词表达“情感、态度、语气等”；情态动词表示 “必要性”等方面的用法。虚拟语气的考点主要集中在名词性从句、条件句中的用法，以及错综条件句中虚拟语气的应用。 专题八 │ 考点荟萃 考点荟萃 一、情态动词表推测的用法
专题八 │ 正面解读 正面解读 专题八 │ 正面解读 情态动词
意义
语气
句式
语境
例句
备注
must 一定
可能性最大
肯定句
对 具 体 事 实 的 判 断 ①A：Look，someone is coming. Who can it be? B: It may be our headmaster. A: It can’t be him. He has gone to Shanghai. B: It must be Mr. Wang. He looks like our headmaster. ②That may not be true. ③He couldn't have discovered the truth.
①对现在的行为或状态的推测：must/may/might/can/could＋do ②对过去的行为或状态的推测：must/may/might/can/could have done
may/might(might可能性小于may) 可能 可能性较小，尤其might最不肯定 肯定句、否定句(可能不) can/could (could可能性小于can) 可能 疑问句、否定句(不可能)、(could有时也用于肯定句) 有时会 肯定句 专题八 │ 正面解读 情态动词
意义
语气
句式
语境
例句
备注
should /ought to 应该 ，理应
理论上 ①It's 8 o'clock now. He should be in the office now.
②Hi, Mum! I'm on the bus. I should be home in about ten minutes.
常表示在一段时间内可能发生的事或某人的期望。一般句末有时间状语，或有语境暗示。所表示的猜测发生的可能性很大。
注意：should (ought to)表示推测是高考考查的重点和难点。如： — When can I come for the photos？I need them tomorrow afternoon. — They ________ be ready by 12：00.
A．can
B．should
C．might
D．need
【解析】 B A项表示推测时常用于否定句和疑问句中。C项表示推测语气不太肯定。should意为“按理说，理应”，既回答了顾客的询问，不失礼貌，又为照片有可能尚未洗好，顾客到时取不到留下了回旋的余地，体现了店主的精明与用词经过仔细推敲。
专题八 │ 正面解读 He is at home. (事实)
He must be at home.（非常肯定的推断）
He could be at home.（很可能）
He ought to be at home.（很可能）
He may be at home.（仅仅可能而已）
He might be at home.（或许, 非常不确定）
He might not be at home.（也许不在家） He may not be at home. （比might可能）
He couldn’t be at home.（很可能不在家）
He can’t be at home.（一定不在家） He isn't at home.（事实） 不同的“肯定”程度可按下列层次排列 情态动词+have done表示对过去情况的推测 （一）should /ought to have done本来应做而未做，表达遗憾感情色彩 例1：I told Sally how to get there,
but perhaps I ____for her.(NMET94)
had to write it out
must have written it out C. should have written it out
D. ought to write it out 析：选C。分析语境可知，口头上告知Sally如何去那里是不够的，所以我本应书面告知，却有没书面告知之，显得应使用should /ought to have written表示遗憾之情。 （二）may/might have done可能已做 / must have done 一定已做/can’t have done不可能做 例1：--- Where is my pen?
--- I _____it.(NMET88)
A. might lose
B. wouldn’t have lost
C. should have lost
D. must have lost D （三） could have done指本来能做而实际未做，表达遗憾的感情色彩.
You could at least have sent five cards.
你本来可以至少寄去5张明信片的。
（说明没有寄那么多）
二、情态动词的其他用法 1．can, could, may, might
专题八 │ 正面解读 情态动词 意义
例句
备注
can/could 能力
①I can see some birds flying in the sky.
②Could the girl read before she went to school?
could表示泛指过去的某一能力。表示过去有能力并且成功地做了某事，通常用was/were able to do，相当于managed to do/succeeded in doing。如：Because he practised hard, he was able to pass the driving test.
专题八 │ 正面解读 情态动词 意义
例句
备注
can/could 允许 (有时可与may互换)
Can/May I have a look at your photos？
can与could、may与might不表时态差异，只是语气上的差别，could/might比can/may更委婉。注意在回答时不能用could/ might。
请求
—Can/Could you lend me a hand？—Yes, I can.
专题八 │ 正面解读 情态动词 意义
例句
备注
may/might 允许或请求
①You may take this if you like. ②May/Might I ask for a photo of your baby？
can与could、may与might不表时态差异，只是语气上的差别，could/might比can/may更委婉。注意在回答时不能用could/ might。
2.must, should
专题八 │ 正面解读 情态动词 意义
例句
备注
must
必须
①We must help each other to overcome the difficulties. ②—Must I finish the work today？—No, you needn't/you don't have to./Yes, you must. ③You mustn't take photos here, and it is forbidden.
①must表示主观意志，have to表示客观。如：They had to speed up, for the weather turned terrible. ②Must I/we…？的否定回答不能用mustn't。
偏要 硬要 非要 ①Why must you always interrupt me？ ②—Can I borrow your car, Mum？—If you must.
表示与说话人愿望相反及不耐烦。
专题八 │ 正面解读 情态动词 意义
例句
备注
should
应该(常与oughtto通用) You should be polite to the old.
ought to 的否定式：ought not to(oughtn't to)；疑问式：Ought …to…？
竟然
It is strange that he should react in this way.
表示惊讶、意外等语气。
万一
①Should anyone phone, tell them I will call back later. (＝ If anyone should phone…)②If I should go there tomorrow, I would go to see her.
用于if从句中强调“万一”，或用于虚拟语气。
3. need, dare
专题八 │ 正面解读 情态动词 例句
注意事项
need ①I needn't go at once.
②—Need you go at once？—Yes，I must. /No, I needn't. ①need可以作实义动词，用于各种句式。如：I need to go at once. I don't need to go at once. —Do you need to go at once？—Yes，I do. ②need作情态动词常用于否定、疑问或条件句中。 dare ①He daren't cross the river. ②How dare you say that to me？ dare和need一样，既可以作情态动词，也可用作实义动词。用作情态动词时，主要用于否定句、疑问句和条件句。用作实义动词时，可用于各种句式。如：He didn't dare (to) go out alone at night. (在否定句中to有时可省略)
4.shall/will/would
专题八 │ 正面解读 情态动词 意义
例句
备注
shall
表示征询意见。
Shall I help you？
用于第一、第三人称疑问句中。
表示说话人的意愿，有“命令，允诺，警告，决心”等意思。
①You shall do as I say. (命令) ②You shall have the book tomorrow. (允诺) ③If you don't get out, I shall knock you down. (警告) 用于第二、第三人称。
4.shall/will/would
专题八 │ 正面解读 情态动词 意义
例句
备注
will/would 表示意愿
①I will do everything for you. ②None is so blind as those who won't see.
表请求
Will/ Would you please close the window？
用于疑问句中。would更委婉
表示某种倾向或习惯性动作
①Fish will die without water. ②Every time she was in trouble，she would turn to him for help. (would指过去某一段时间的情况，常与表示过去的时间状语连用，意为“总是，总会”，后面只能接动作性的动词。)
used to表示与现在的情况相反，表示“过去如此而现在不再这样”。其后既可接表动作的动词，也可接表状态的动词。如：There used to be an apple tree in front of the house. 4.shall/will/would
专题八 │ 正面解读 情态动词 意义
例句
备注
will/would 表示功能(能，行)
①If you don't have a pen, a pencil will do. ② We tried the door again，but it wouldn't open.
与否定词连用常表示“拒绝”。
表示推测(可能、大概)
①This will be the house you are looking for. ②I would be about ten when my father left home. 三、情态动词＋have done
专题八 │ 正面解读 情态动词 意义
例句
备注
must have done；may/might have done；can/could have done 一定(肯定句)；可能(肯定句和否定句)；可能(疑问句和否定句) You can't/couldn't have met my grandmother. She died before you were born.
对过去的事情的推测
might have done; could have done；would have done 本来可能做……而未做；本可以做……而未做；本来会做……而未做 ①He might have given you more help, even though he was very busy.②We could have walked there, and it was so near. 与过去事实相反的虚拟表达
专题八 │ 正面解读 情态动词 意义
例句
备注
should/ought to have done 本应该做……而未做
Your brother has failed English exam again. You ought to have given him more help.
表示责备 needn't have done 本不需要做……但却做了 You needn't have wakened me up; I don't have to go to work today. He must be reading, ____ he? You must do it yourself, ____ you? He must have gone over the article,
______he? It must have rained last night, _____ it? 表猜测语气的反意疑问句的构成 isn’t don’t hasn’t didn’t 可兼做行为动词的情态动词：need 、 dare
情态动词 (+动词原形) 行为动词
. need dare 2.尤其用于： *否定句及疑问句中;
3.常以needn’t 和daren’t
的形式出现; 4.dare有其过去时dared.
多用于肯定句;
(sb.) need to do
dare to do (sth.) need to be
done
(sth.) need doing
判断正误:
How dare you say such a thing?
How dare you to say such a thing? He daren’t to speak English before such a
crowd, did he?
He daren’t speak English before such a
crowd, dare he? Nobody need to be afraid of catching the disease.
Nobody need be afraid of catching the disease.
need 的被动含义：need，want, require, worth (adj.)后面接doing 也可表示被动,
need doing =need to be done
四、虚拟语气
虚拟语气表示说话人所说的话不是事实，而是一种假设、愿望、怀疑或推测。 1． 虚拟语气在条件句中的用法
专题八 │ 正面解读 专题八 │ 正面解读 if从句 主句 与现在事实相反 if＋主语＋动词过去式 主语＋should/would/could/might＋动词原形 与过去事实相反 If ＋主语＋had＋过去分词 主语＋should/would/could/might＋ have＋ 过去分词 与将来事实相反 (1) if＋主语＋动词过去式 主语＋should/would/could/ might＋动词原形 (2)if＋主语＋were to＋动词原形 (3) if＋主语＋should＋动词原形
If it were to rain tomorrow, I should not drive my car. 如果明天下雨的话，我就不开车了。(明天的情况还不知道)
If I had done it in time, I should have had a good time. 如果我及时做的话，日子就好过多了。(可惜当时没能及时做)
注意： (1) 主句中的should通常用于第一人称，would可用于任何人称。 (2) 条件句中如果动词是be，其过去式所有人称的单复数都可用were；在第一、三人称单数的口语中，可用was代替were。但在if I were you中，不能说成if I was you。 专题八 │ 正面解读 (3) 当条件从句的行为与主句所表示的行为所发生的时间不一致时，主从句中动词的形式要根据它所标示的时间作出相应的调整，这就是所谓的“错综条件虚拟语气”。如：
If they had studied hard, they could do it easily now. 如果他们以前努力学习的话，现在干得就会容易些了。
If he had not taken my advice, he wouldn't do it much better like this.
如果他不听我的建议，他就不会干得这么好了。 (4) 在条件句中，如果有were, had, should等，则可省略if，但应注意把were, had, should等提到从句主语之前。
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