情态动词和虚拟语气重点与难点
情态动词和虚拟语气
情态动词
（一）表示推测的情态动词
对现在或将来情况推测，用情态动词+do / be / be doing…；对过去的推测，用情态动词+have done / been…；表示肯定推测的情态动词must, should / ought to, may, might, 否定推测，常用can’t / couldn’t，译为“根本不可能”、“想必不会”，表示推测的语气非常肯定，may not, might not译为“可能不”、“也许不”，表示推测的语气不很肯定。
(1) must表示推测，意为“一定……”，只能用于肯定句中。must have done意为：一定做过某事或某事肯定发生了。例如：
(NMET2007 江苏)—She looks very happy. She ______ have passed the exam.
—I guess so. It’s not difficult after all.
A. should
B. could
C. must
D. might
【解析】句意为：她看上去很高兴，一定是通过了考试。
【答案】C
(2) should (not) / ought (not) to在中表示根据常规或常识推测，表示“某事应该或不应该发生”。例如：(NMET2007全国I)—How’s your tour around the North Lake? Is it beautiful?
—It ________ be, but it is now heavily polluted.
A. will
B. would
C. should
D. must
【解析】should此处表示推测，意为“应该”。
【答案】C
②(NMET2005上海)There _________ be any difficulty about passing the road test since you have practiced a lot in the driving school.
A. mustn’t
B. shan’t
C. shouldn’t
D. needn’t
【解析】句意：既然你在驾校进行了大量训练，那么通过道路测试按理不应该有困难。
【答案】C
(3) can, could表达推测时，一般用于疑问句和否定句中；can用于肯定句中表示一种理论上的可能性，并不牵涉是否真的会发生，在这种用法中can只能与动词原形连用
例如：
①（NMET2008浙江）You ______ be hungry already — you had lunch only two hours ago!
A. wouldn’t
B. can’t
C. mustn’t
D. needn’t
②（NMET2008天津）She ______ have left school, for her bike is still here.
A. can’t
B. wouldn’t
C. shouldn’t
D. needn’t
③（NMET2008福建）It is usually warm in my hometown in March, but it _____ be rather cold sometimes.
A. must
B. can
C. should
D. would
④（NMET2008辽宁）Peter ____ be really difficult at times even though he’s a nice person in general.
A. shall
B. should
C. can
D. must
【解析】①②两个考题中can用于表示否定的推测，意为：不可能，一定不会；③④两个考题中can表示理论上的可能性，翻译为：有时候会……。
【答案】① B ② A ③ B ④ C
(4)may (not) / might (not)表达一种不太把握的推测，意为“或许，可能”
例如：
① (NMET2008全国II) Liza ___ well not want to go on the trip --- she hates traveling.
A. will
B. can
C. must
D. may
【解析】may well为固定搭配，意为：很可能，极有可能。
【答案】Ｄ
② (NMET2008四川) Although this ____ sound like a simple task, great care is needed.
A. must
B. may
C. shall
D. should
【解析】这听起来或许是一项简单的任务，但却需要极大的细心。
【答案】B
③ (NMET2008重庆)—I can’t find my purse anywhere.
—You __ have lost it while shopping.
A. may
B. can
C. should
D. would
【解析】结合语境可知，回答者是在提醒对方：或许购物时把钱包丢了。
【答案】A
（二）表达虚拟语气的情态动词
对过去的一种结果的假设或虚拟，用情态动词+have done这一结构，常用的有以下几个情态动词：(1) should (not) / ought (not) to have done本（不）应该做某事，但却没有做或做了，含有责备或后悔之意。例如：
（NMET2008江苏）—I’m sorry. I _________at you the other day.
—Forget it. I was a bit out of control myself.
A. shouldn’t shout
B. shouldn’t have shouted
C. mustn’t shout C. mustn’t have shouted
【解析】对不起，我那天本不应该对你大喊大叫的。
【答案】B
(2) could have done本来能够做某事但未做。例如：
（NMET2008山东）Thank you for all your hard work last week. I don’t think we ______ it without you.
A. can manage
B. could have managed
C. could manage
D. can have managed
【解析】根据题干中所给出的时间last week可知我们已经做完了工作，已经完成，故排除A、C 两项，再结合could have done表示虚拟语气以及与前面的I don’t think…，故说话者想表达的意思是：离开了你，我们本不可能完成这项工作。
【答案】B
(3) needn’t have done本没有必要做某事但却做了。要注意needn’t do则表达“没有必要去做某事”，时间上应该是现在或将来。例如：
①(NMET2005福建)—Catherine, I have cleaned the room for you.
—Thanks. You ________ it. I could manage it myself.
A. needn’t do
B. needn’t have done
C. mustn’t do
D. shouldn’t have done
【解析】根据句意可知Catherine对对方为她打扫了房间表示感谢并提到对方不必为她打扫房间。【答案】B
②(NMET2007上海春) The boss has given everyone a special holiday, so we go to work tomorrow.
A. can’t
B. mustn’t
C. needn’t
D. shouldn’t
【解析】老板给所有的员工放了假，所以我们明天不必再去上班。
【答案】C
(4)would (not) have done本来(不)会发生某事，但却（发生了）或没有发生。常用于虚拟条件句或含蓄虚拟条件引导的虚拟语气，表示对过去所发生事情结果的假设。例如：
(NMET2001上海春) He hesitated for a moment before kicking the ball, otherwise, he ________ a goal.
A. had scored
B. scored
C. would score
D. would have scored
【解析】句中otherwise为含蓄条件，相当于if he had not hesitated for a moment before kicking the ball，这是对过去的一种虚拟假设。
【答案】D
(5) might have done表示“本来可能……”，但实际上没有发生的事。例如：
(NMET2008江西)What a pity! Considering his ability and experience, he ________ better.
A. need have done
B. must have done
C. can have done
D. might have done
【解析】真是可惜！考虑到他的能力和经验，他本来可以做得更好的。
【答案】D
（三）表达“情感、态度、语气” 等方面的情态动词
1. must表达“情感、态度、语气”主要有以下用法：
(1) 表示主观的义务和必要，主要用于肯定句和疑问句，意思为“必须……，得……，要……”；由must引起的疑问句，肯定回答要用must或have to，否定回答要用needn’t或don’t have to,意思是“不必”。另外，must与have to都可以表示“必须”这一含义。must表示一种主观的需要，而have to表示一种客观的需要，意思是“不得不”，其否定形式是don’ have to。
例如：(NMET2008陕西)-What sort of house do you want to have? Something big?
--Well, it ______ be big--that's not important.
A. mustn't
B. needn't
C. can't
D. won't
【解析】Something big?此处意为：Must it be big? 回答者的意思是：房子不必太大—那并不重要。【答案】B
(2) must的否定形式mustn’t表示禁止，意思是“不能，不许”。例如：
(2008上海春)When I was young, I was told that I ______ play with matches
A. wouldn't
B. needn't
C. mustn't
D. daren't 【解析】当我年轻的时候，（家人）就一直告诫我千万不要玩火柴。
【答案】C
(3) must用于条件句或疑问句中，可以用来表示责备、抱怨的感情色彩，意思为“偏要，硬要、干嘛”。例如：
①（NMET2006山东）—May I smoke here ?
—If you ____, choose a seat in the smoking section.
A. should
B. could
C. may
D. must
②（NMET2005全国Ⅲ）John, look at the time. ___________ you play the piano at such a late hour?
A．Must B．Can C．May D．Need
【解析】must在这两道试题中均表示“非得，偏要”。
【答案】① D ② A
2. should
(1) should应该，表示“责任和义务”。例如：
(NMET2008上海) According to the air traffic rules, you ___ switch off your mobile phone before boarding.
A. may
B. can
C. would
D. should
【解析】should此处表示根据交通法规应尽的责任和义务。
【答案】D
(2) 在虚拟条件句中用以加强假设语气，表示“与将来事实相反的假设”，用If+主语+ should +动词原形，当“万一(会)”讲。这时可省略if，将should提到句首，变为倒装句式。请看下面的例子：
If it should rain (=Should it rain) tomorrow, I would stay at home.万一明天下雨的话，我就待在家里。再如：
(NMET2006湖北)________ fired, your health care and other benefits will not be immediately cut off.
A. Would you be
B. Should you be
C. Could you be
D. Might you be
【解析】句意：万一你被解雇，给你的医疗救助和其它方面的福利也不会被取消。
【答案】B
(3) should还可以用来表示说话人对某事不能理解、感到意外、惊异等意思，译为“竟然，竟会”。例如：
(NMET2001上海)You can’t imagine that a well-behaved gentleman _____ be so rude to a lady.
A. might
B. need
C. should
D. would
【解析】句意：你想象不到这么一个表现良好的绅士竟然会对一个女士这么粗鲁。
【答案】C
3. shall
(1) shall用于第一和第三人称，常用于疑问句中，用来征求对方意见。例如：
① (NMET2006北京)—What’s the name?
—Khulaifi. _________ I spell it for you?
A. Shall
B. Would
C. Can
D. Might
【答案】A
(2) 用于第二和第三人称，表示“命令、威胁、警告、允诺、”等。例如：
（NMET2004，湖南,28）—Excuse me. But I want to use your computer to type a report.
—You _____have my computer if you don’t take care of it .
A. shan’t
B. might not
C. needn’t
D. shouldn’t
【解析】shall此处表示“警告”。
【答案】A
(3) shall也用于宣布法律、规定的要求。例如：
① (NMET2007 四川)—What does the sign over there read?
—“No person ________ smoke or carry a lighted cigarette，cigar or pipe in this area.”
A. will
B. may
C. shall
D. must
【解析】禁止吸烟是此处的规定。
【答案】C
4. can
(1) can可以用来表示惊异、怀疑、不相信的态度，主要用于否定句、疑问句或感叹句中。例如：(NMET2003全国) How ______ you say that you really understand the whole story if you have only covered only part of the article?
A. can
B. must
C. need
D. may
【答案】A
(2) can也可以用来表示请求或许可。例如：
（NMET2004，辽宁）—Mum, I’ve been studying English since 8 o’clock.. ______I go out and play with Tom for a while?
—No, I’m afraid not. Besides, it’s raining outside now.
A. Can’t
B. Wouldn’t
C. May not
D. Won’t
【答案】A
(3) can可以表达一般的或永久的能力。be able to也可表达能力，但常用来表达在某件事情中所表现出来的能力，尤指克服困难能够完成某事。例如：
① (NMET2006福建) If it were not for the fact that she ______ sing, I would invite her to the party.
A. couldn’t
B. shouldn’t
C. can’t
D. might not
② (NMET1997) The fire spread through the hotel very quickly but everyone ______ get out.
A. had to
B. would
C. could
D. was able to
【答案】C D
5. would
(1)will与would可表示“意愿；意志”。
例如：(NMET2008北京) John promised his doctor he _____ not smoke and he has never smoked ever since.
A. might
B. should
C. could
D. would
【解析】根据promise可知此处是John向医生表明自己的意志。
【答案】D (2) would表示过去倾向性或习惯性的动作。used to 也有这一用法，但used to即可用来表达过去的习惯性的动作，也可用来表示过去的状态。例如：
① (NMET1996上海)When he was there, he ___ go to that coffee shop at the corner after work every day.
A. would
B. should
C. had better
D. might
② (NMET2007安徽)In my opinion, life in the twenty-first century is much easier than ________.
A. that used to be
B. it is used to
C. it was used to
D. it used to be
【解析】第一题would指过去习惯性的动作；第二题it 替代life, used to be 指过去的样子。
【答案】A D
虚拟语气
一、考点聚焦
1、虚拟语气用于条件状语从句中
（1）表示与现在事实相反的假设，条件状语从句中的谓语动词用“过去式（be动词的过去式用were）”，而主句中的谓语动词用“would / should/ could / might + 动词原形”。如：If I were a boy, I would join the army.
If the had time, she should go with you.
（2）表示与过去的事实相反，条件状语从句中的谓语动词用过去完成时，主句中的谓语动词则用“would / should / might / could + have +过去分词”。如：
If he had taken my advice, he would have succeeded in the competition.
（3）表示与将来事实相反，条件状语从句中的谓语动词一般过去时或should(were to) + 动词原形，而主句中的谓语动词则用would / should/could might + 动词原形。如；
If it were to rain tomorrow, the football match would be put off.
（4）当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时，动词的形式要根据它所表示的时间作相应调整。如：
If they had worked hard, they would be very tired.(从句说的是过去，主句指的是现在)
有时在使用时可省略if,句子则可换成下列形式，即“were / had / should +主语”。如：
Were I a boy, I would join the army.
Had he taken my advice, he would have succeeded.
Were it not for the expense, I would go to Britain.
2、虚拟语气用于名词性从句
（1）虚拟语气在宾语从句中的运用。
①“wish + 宾语从句”表示不能实现的愿望，译为“要是……就好了”等。表示现在不能实现的愿望，从句中的谓语动词用一般过去时；表示将来不能实现的愿望，从句中的谓语动词用“would/could + 动词原形”；表示过去不能实现的愿望，从句中的谓语动词用“had + 过去分词”或“could(should) + have + 过去分词”。如：
I wish it were spring all the year round.
I wish I had known the answer.
I wish I could fly like a bird.
②在表示建议、要求、命令等的动词suggest、advise、propose、demand、require、insist request、command、order等后的宾语从句中，谓语动词用should + 动词原形或是动词原形。如：She suggested we (should)leave here at once.
The doctor ordered she should be operated.
（2）虚拟语气在同位语从句和表语从句中的运用。
作表示建议、要求、命令等的名词advise、idea、order、demand、plan、proposal、suggestion、request等的表语从句和同位语从句，从句中的谓语动词用“（should）+ 动词原形”。如：His suggestion that we (should)go to Shanghai is wonderful.
My idea is that they (should)pay 100 dollars.
（3）虚拟语气在主语从句中的运用。
在主语从句中，谓语动词的虚拟语气用“should + 动词原形”的结构，表示惊奇、不相信、理应如此等。如：
It is necessary(important, natural, strange, etc.)that we should clean the room every day.
It was a pity (a shame, no wonder, etc.)that you should be so careless.
It will be desired(suggested, decided, ordered, requested, proposed, etc.)that she should finish her homework this afternoon.
注意：这种从句表示的是事实。如果说人对这种事实表现出惊奇的情感，就可用虚拟语气。反之，如果不表示惊奇等情感，that从句也可用陈述句语气。如：
It is pity that you can’t swim.
3、虚拟语气在其他场合的运用
（1）虚拟语气在as if/as though、even if/even though等引导的表语从句或状语从句中，如果从句表示的动作发生在过去，用过去完成时；指现在状况，则用一般过去时；指将来状况则用过去将来时。如：
He did it as if he were an expert.
Even if she were here, she could not solve the problem.
（2）虚拟语气用于定语从句中。
这种从句常用于句型“It is (high)time (that) … ”中，定语从句的谓语动词用一般过去时(be用were)或should + 动词原形，意思是“(现在)该……”。如：
It’s time that I picked up my daughter.
It’s high time we were going.
（3）虚拟语气用在if only引导的感叹句中。如：
If only I were a bird.
If only I had taken his advice.
二、经典名题导解
选择填空
1. When a pencil is partly in a glass of water, it looks as if it _______. (NMET 95)
A. breaks
B. has broken
C. were broken
D. had been broken
解析：答案为C。本题考查的是as if 引导的让步状语从句中的语气问题，as if引导的状语从句如果与事实一致，不用虚拟语气，如果与事实相反，应用虚拟语气。题中“当铅笔的一部分浸在水中，铅笔看上去好像断了”。而实际上铅笔并未断，与事实相反，前半部分陈述是一般现在时，因而本句是对一般现在时的虚拟，用were broken。
2. I didn’t see your sister at the meeting. If she ___________, she would have met my brother.(NMET 94)
A. has come
B. did come
C. came
D. had come
解析：答案为D。本题考查的是if条件句中的虚拟语气。题意是：我在会议上没看到你姐姐，故你姐姐没来。因此如果“她来了”与事实相反，前面一句交代了虚拟语气的时态是一般过去时的虚拟，所以if从句中用had+过去分词。
3. —If he ___________, he ________that food.
—Luckily he was sent to the hospital immediately.(NMET 93)
A. was warned; would not take
B. had been warned; would not have taken
C. would be warned; had not taken
D. would have been warned; had not taken
解析：答案为B。本题考查的是条件状语从句与主句表示与事实相反时虚拟语气的用法。根据下一句语境可知，他事先并没有得到警告，表示过去时间的虚拟语气，故选B。
巩固练习
1．You are late．If you a few minutes earlier, you him．
A．came；would meet B．had come；would have met
C．come；will meet D．had come；would meet
2. We might have failed if you us a helping hand．
A．have not given B．would not give C．had not given D．did not give 3．The law requires that everyone his car checked at least once a month．A．has B．have C．had D．will have
4．If there were no subjunctive mood，English much easier．
A．will be B．would have been C．could have been D．would be
5．Look! What you’ve done! You have been more careful．
A．should B．may C．ought D．would
6．Without electricity，what ?
A．will the world be like B．would the world be like
C．the world will be like D．the World Would be like
7．With your ability，you out the puzzle within a few minutes．
A．could have worked B．need have worked
C．ought have worked D．must have worked
8. My suggestion is that the sick boy to hospital as soon as possible．
A．is taken B．must be taken C．be taken D．has to be taken
9．If we had not missed the bus，we lunch at home now．
A．would have had B．would have C．must be having D．would be having 10．here yesterday，he would attend the lecture with us today．
A．Had he been B．If he were C．Were he D．Should be he
11．Do you feel that I the problem in a different way the other day?
A．should come B．should have solved C．have solved D．solved
12．0ur chairman hasn’t come yet．If he on time，we would have to put off the meeting．A．should come B．would come C．shouldn’t come D．doesn’t come．13．He did his best in everything；he would not have been what he was．A．and B．but C．otherwise D．but that
14．---Excuse me, but I want to use your computer to type a report.
----You_______ have my c omputer if you don’t take care of it.
A. shan’t
B. might not
C. needn’t
D. shouldn’t
15．The teacher requires Rose by heart 15 English words each day．
A．1earn B．to learn C．must learn D．1earning
16．—If he ，he that food．
—Luckily he was sent to the hospita1 immediate1y．
A．was warmed；would not take B．had been warmed；wou1d not have taken
C．would be warmed；had not taken D．would have been warmed；had not taken
17. Why didn't you tell me there was no meeting today? I _____ all the way here _____ the heavy snow.
A. needn't have driven；through
B. can't have driven；across
C. mustn't have driven；through
D. shouldn't have driven；cross
18. —Mum, it’s none of my business. Why _____ I care?
— Just because she is your sister.
A. can
B. should
C. will
D. may
19. —I didn’t know you were good friends .
—You _____.I have known her since she moved here. You were studying abroad then.
A. may have
B. ne edn’t have
C. couldn’t have
D. must have
20. —The concert was wonderful!
—Really? How I wish I ______to the theatre with you yesterday!
A. had gone
B. might go
C. were able to go
D. would go
21.The two strangers have been talking in the park for a long time as though they ______old friends.
A. are
B. should be
C. were
D. would be
22. ______the heavy rain, we ______the town.
A. But for; should have reached
B. Because of; would have reached
C. During the period of; we would reach
D. In spite of; we should have reached
23. —If William _______, he _______that green peach.
—Luckily he was sent to the hospital in time.
A. was warned; would not take
B. had been warned; would not have taken
C. would be warned; had not taken
D. would have been warned; had not taken
24. —Is it good to look up every new word when I come across it in reading?
—No. You ______because you are likely to guess the meaning from the context.
A. c an’t
B. mustn’t
C. don’t have to
D. ought not to
25. —______I use your computer to send an e-mail?
—Yes, you ______. But you mustn’t keep it too long.I’ll surf the Internet after supper.
A. Could; could
B. Could; must
C. Can; can
D. Could; can
26. When he lived there, he ______go to that book shop at the corner with his girlfriend after work every
day.
A. would
B. should
C. had better
D. might
27.—I hear you’ve got a set o f Australian coins. ______I have a look?
— Yes, certainly.
A. Do
B. May
C. Shall
D. Should
28. — What happened to the young trees we planted last week?
—The trees______ well , but I didn’t water them.
A. might grow
B. needn’t have grown
C. would grow
D. would have grown
29. What ______ had Bob walked farther, as far as the river bank?
A. would happen
B. could happen
C. would have happened
D. needn’t have happened
30. Hurry up, Tom. It’s high time we______ to the t heater.
A. will
B. shall
C. are going to
D. went
31. —Do you think he will do me a favor?
— As far as I know, he is the last one to help others. He______be prepared to give you a hand, though.
A. might
B. must
C. can
D. should
32. Even though I’d hurt my leg, I______ swim back to the river bank.
A. could
B. might
C. had to
D. was able to
33.— It is rather cold here. Shall we light a fire?
— No, we______ because things are easy to catch fire.
A. won’t
B. can’t
C. mustn’t
D. needn’t
34.—Would you have told him the answer had it been possible?
—I would have, but I ______so busy then.
A. had been
B. were
C. was
D. would be
35. The young man insisted that he______ these watches and_____ _free.
A. stole, set
B. had stolen, be set
C. steal, be set
D. had stolen；must be set
36. I ______your address, otherwise I______ you long before.
A. had forgotten, had visited
B. forgot, have visited
C. forgot, would have visited
D. have forgotten, would visit
37. I______ you a beautiful present for your birthday, but I was short of money at that time.
A. would buy
B. had bought
C. would like to have bought
D. must have bought
38.—Do you feel like ________ there or shall we take a bus?
—I’d like to walk. But since there isn't much time left, I'd rather we________ a taxi.
A. walking, hire
B. to walk, hire
C. to walk, hired
D. walking, hired
39. —Miss White has decided to explore in the forest by herself.
—She________ ask her boyfriend to if she ________go walking in the forest.
A. needn't to, dares to http:/
B. doesn't need, dares
C. need not to, dare to
D. needn't , dare
40. His failure in the exam suggested that he __________ the teacher’s instructions.
A. can’t have followed http:/
B. needn’t have followed
C. mustn’t have followed
D. shouldn’t have followed
41.I _________ you, but I didn’t think you would listen to me.
A. could have told
B. must have told
C. should tell
D. might tell
42. The manager’s health was getting worse and worse because of heavy burden，so the doctor strongly recommended that he a holiday.
A. took
B. would take
C. must take
D. take
43. —It’s so cold! Why not close the door?
—Sorry. It .I’ll have it repaired soon.
A. won’t shut
B. won’t be shut
C. hasn’t shut
D. isn’t shut
44. I wouldn’t marry Pat even if she_________the last woman on earth.
A. is
B. was
C. had been
D. were
45. Many students will take part in the school sports meeting this week, so she suggested that the class meeting _______ held on Saturday .
A. not be
B. not to be
C. be not
D. be not to
46.________the problem, he wouldn't have committed those mistakes.
A. If he understood
B. Had he understood
C. When he had understood
D. If he would understood
47. —But those are size 44. You might need a smaller size.
—Yes, I ______ a bit of weight. I have been trying to lose weight!
A. will have lost
B. should have lost
C. may have lost
D. can’t lose
48.—Are you going to Lloyd’s birthday party on Friday?
— Only if it ______, he said he was having a picnic party.
A. wouldn’t rain
B. doesn’t rain
C. won’t rain
D. hadn’t rained
49. If Sanlu Group __________melamine to the milk, the babies ________ too much from kidney stones.
A. didn’t add; would not suffered
B. hadn’t added; wouldn’t have suffered
C. hasn’t added; wouldn’t have suffered
D. hadn’t added; would have suffered
50.—The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job?
—____ my students have a try?
A. Shall
B. Will
C. Could
D. Should
真实条件句,虚拟语气.
当我们陈述了一个事实，而又不是很有把握，就可以在陈述句后加一个简短问句，称为反意疑问句。首先看以下例句：（1） You like calssical music, don't you? 你也喜欢古典音乐，对吗？(2 He lived in Vienna, too,didn't he? 他也住在维也纳，对吗？（3）Your parents can swim, can't they? 你父母会游泳，是吗？（4） Tony doesn't like classical music,does he? 托尼不喜欢古典音乐，对吗？（5） This music isn't very popular, is it? 这音乐并非十分流行，对吗？从以上句子可以看出，反意疑问句是由“助动词/ 系动词be（肯定或否定）+主语（代词）” 构成的。在反意疑问句的构成中要注意以下几点： 1.前面当陈述句如果是肯定的，反意疑问句就要用否定形式，如（1）、（2）、（3）；前面的陈述句如果是否定的，反意疑问句就要用肯定形式，如（4）、（5）； 2.反意疑问句的主语必须是代替前面主语的代词； 3.翻译疑问句的谓语动词在时态和人称上要与前面陈述句谓语动词保持一致。陈述句部分如果有标识否定意义的词，反意疑问句要用肯定式。如：They have never visited his home, have they? 他们从来没有到他家玩过，是吧？在回答反意疑问句时，要特别注意英、汉两种语言习惯的差别。试看下面当例句：——Mr Smith isn't American, is he? 史密斯先生不是美国人，对吧？——Oh yes, he is.不对，他是美国人。可以看出，在英语中，无论问题是怎样问的，只要答语的事实是肯定句，就要用YES；只要答语的事实是否定的，就要用NO. 编辑本段英语18种特殊的反意疑问句介绍 1.祈使句。祈使句后一般加上will you或won't you构成反意疑问句，用will you 多表示“请求”，用won't you 多表示提醒对方注意。例如：Look at the blackboard, will you/ won't you?看黑板，好吗？Let引导的祈使句有两种情况：1Let's...,后的反意疑问句用shall we或shan't we。例如：Let's go home, shall we/ shan't we? 回家吧，好吗？还可以用may I来表示征求对方的同意或许可。2Let us/me...后的反意疑问句用will you或won't you。例如： Let me have a try, will you/won't you? 让我试一试，行吗？ 2.感叹句。感叹句后加反意疑问句时，其反意疑问句需用be的一般现在时态的否定形式。例如：What fine weather, isn't it? 多好的天气啊，是吧？ 3. 当陈述部分谓语动词是need, dare, used to，且这些词被用作实义动词时，其反意疑问句需用do的适当形
情态动词和虚拟语气难点解析
情态动词和虚拟语气难点解析 一、 Shall 的用法 :表示请求、允诺、允许 当对方是决策者时,你代表你(们自己(I , we ,或代表第三者(he , she , they 向对方(you 请示或提出建议时用 (用于第一、三人称, 构成疑问句, 征求对方意见,此意不用 will :① shall I/we… ?② shall he/she/they(也可以是表示第三人称的名词…? ③would/can you… ? …… 好吗?要不要…… ? 如: Shall we begin our class ? Shall I open the window ? Shall the boy wait ? 你要那孩子等吗? Let’s sit here ,shall we ? 我们坐在这里,好吗? When shall my father be able to leave hospital ? Would you do me a fovor ?你能帮我一个忙吗? 当你自己(I 是决策者时,给对方(you 或第三者(he , she , they 以命令、警告、允诺或威胁时, 要用 shall 。此外, 当宣布法律、规定时, 也用 shall 。如: You shall leave the room at once ,and he also shall .(= I order you and him to leave the room at once . It has been anounced that candidates shall remain in their seats until all the papers
情态动词与虚拟语气
情态动词与虚拟语气 【语法要点】 情态动词 所谓情态动词是指它含有一定的含义，可以表达某种感情和说话的语气，但是它不可以单独使用 作谓语动词。学习情态动词主要学习英语国家的语言习惯和表达法，特别是在口语中不要过分追求原理，更不要不根据说话场合而进行推理，编造出一些语法结构正确的中文式英语。 一、情态动词的类型 1.只作情态动词的有：must、can、could、may、might、ought to 2.既可作情态动词又可作实义动词的有：need、dare 3.既可作情态动词又可作助动词的有：shall、should、will、would 二、情态动词的特征 1.表示说话人的情感态度，不能单独作谓语，与行为动词或连系动词一起作谓语。 2.情态动词没有人称和数的变化，后接动词原形。 3.具有助动词的特征：可用来构成否定句、疑问句或简短答语。 三、情态动词的用法 1.表示能力 （1）表示现在的能力，用can 或be able to。表示一般的能力时多用can，表示“经过努力成功 的做成某事”用be able to。 （2）表示过去的能力，用could或was/were be able to。区别同上。 （3）表示将来的能力，用will be able to。 2.表示推测、可能性 （1）can 用在肯定句中表示客观的可能性，而不表示具体事情实际发生的可能性。 例如：Accidents can happy on such rainy days. （2）表示具体事情实际发生的可能性的情态动词，其表示可能性的层次如下表： 情态动词肯定式否定式疑问式 must 必定、必然、一定 will 很可能、大概不会、不该会,,吗？ would 可能性较will 小不会、不该（较won’t 弱）会,,吗？（较will 弱） should 应该会、理应（表示合乎理想的情况或结果） ought to 与should 同义 can 一定不会、不可能（否定推测）有可能吗？ could 可疑的可能不可能（与can’t 同义）有可能吗？（较can 弱）may 或许、可能、说不定可能不 might 或许、可能（较may 弱）可能不（较may not 弱） 注意→（1）may，must 常用于肯定句，一般不用于否定句和疑问句。 （2）can 常用于否定句，疑问句和感叹句中，表示疑惑、惊讶或不相信等意思。could 既可用于肯定句，又可用于否定句、疑问句中。
情态动词虚拟语气练习及答案
@ 情态动词和虚拟语气 1. Jack descried his father, who ________a brave boy many years ago, as a strong-wiled man A. would be B. would have been C. must be D. must have been ） 2. —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 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 4. You_______ buy a gift, but you can if you want to. A. must B. mustn't C. have to D. don't have to 5. —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 w_w w. k#s 6. I have told you the truth I keep repeating it A. Must B. Can C. May D. Will ~ 7. Doctors say that exercise is important for health, but it _______ be regular exercise. A. can B. will C. must D. may 8. Just be patient. You ________ expect the world to change so soon. A. can’t B. needn’t C. may not D. will not 9. I’m afraid Mr. Harding ________ see you now. He’s busy. A. can’t B. mustn’t C. shouldn’t D. needn’t 10. I _______ have watched that movie—it’ll give me horrible dreams. A. shouldn’t B. needn’t C. couldn’t D. mustn’t < 11. –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 12. —Sorry, Professor Smith. I didn't finish the assignment yesterday. — Oh, you _________ have done it as yesterday was the deadline. A. must B. mustn't C. should D. shouldn't 13. — _______ I take the book out —I'm afraid not. *
陈述语气、祈使语气和虚拟语气的分类
一、语气的分类 英语的动词一般可带三种不同的语气: 陈述语气、祈使语气和虚拟语气。不同的语气用 动词的不同形式来表示。 陈述语气I went to the theatre yesterday.Jack hadn’t come back home yet. 祈使语气Let’s go.Don’t touch anything on the table until the bell rings. 虚拟语气If I were you, I would not leave her alone. Our teacher suggested that we go to the library this afternoon. 一、虚拟语气在条件状语从句中的用法 条件从句If 从句的谓语形式主句的谓语形式 现在V+ ed (were) would/could/should/might +V (原) 过去had done would/could/should/might+hav e+p.p. 将来 1. V. + ed.2. should+ V.(原)3. were to do would/could/should/might +V.(原) 如果现在不下雨的话, 我们就出去野餐了。If it were not raining, we should go for a picnic. 如果他来这儿, 他就能够帮助你了。If he came here, he might be able to help you. 要是当初她被邀请的话，她就会去参加这次聚会了。She would have gone to the party if she had been invited. 今天早上，她要是不叫我的话，我就会睡过头了。If she hadn’t called me, I would have overslept this morning. 明年我要是二十岁，我就会学法语。If I were to be twenty years old next year, I would take the course of French. 要是失败了，我会再试一次。If it should fail, I would try again. 1. 如果你早来5分钟,你就赶上这趟车了。If you __had got_____ here five minutes earlier, you ____would have caught_____ the bus. 2.如果我现在不忙,我就来帮你了。If I __were__ not busy, I ______would help____ you now. 3. 如果明天下雪了,我们怎么办？What __should____ we do if it ___were to snow_________omorrow? 二、虚拟语气特殊句型: 1. wish 的宾语从句现在: 过去时(were) 过去: 过去完成时(had done) 未来: would/could/might +V.(原) should 我现在要是年轻十岁就好了。I wish I were ten years younger now. 我昨天要是遇见他 就好了。I wish I had met him yesterday. 我希望成为一名科学家。I wish I would be a scientist. 2. would rather that 现在:过去时过去:过去完成时未来:过去时 I would rather you paid me now. I would rather I hadn’t come yesterday. I would rather you came tomorrow. 3. as if /though + 从句现在：过去时过去：过去完成时 She loves the baby as if it were her own son. I remember the whole thing as if it had happened yesterday. 他们就像多年的朋友一样交谈。They talked as if they had been friends for years.
复习专题 虚拟语气难点汇总
复习专题虚拟语气难点汇总 一、初中英语虚拟语气 1．If I were invited to the party，I _______ a red skirt. A． will wear B． wear C． would wear 【答案】C 【解析】 试题分析：如果我被邀请参加聚会，我会穿红色的裙子。此处考查虚拟语气。句中，主句和从句的谓语都要用虚拟语气，与现在事实相反的假设，从句（条件句）动词过去式（be 一般用were）;主句（结果句） should /would/ could/ might +动词原形。故答案为C。 考点：考查虚拟语气。 2．If I______ you, I would take a small present.. A．am B．was C．were D．are 【答案】C 【解析】 试题分析：句意：如果我我你，我会那个小的礼物。句中用虚拟语气，系动词用were，故选C。 考点：考查虚拟语气。 3． If I ＿＿you . I＿＿study harder. A．am , will B．was, would C．were, would D．were, will 【答案】C 【解析】 试题分析：句意：如果我是你，我会更努力学习。这个句子要用虚拟语气，表示与事实相反。所以用过去式were, would,故选C。 考点：考查虚拟语气。 4．If I ______ you, I ______invite him to go to see a movie. A．am;would B．were;will C．were;would D．was;will 【答案】C 【解析】 试题分析：句意：如果我是你，我会邀请他去看电影。go to see a movie去看电影；invite sb to do邀请某人做某事；在表达与现在事实相反的虚拟语气中，Be用were,主句用would。 考点：考查虚拟语气。 5．If I ___ you, I ___ be afraid . A．was, wouldn’t B．were, won’t C．were, wouldn’t 【答案】C
从语言的人际功能看虚拟语气与陈述语气的差异
摘要：从语用学的角度看，虚拟语气具有陈述语气无法企及的“附愿”功能，从语言的这一人际功能研究语气的变异能够揭示虚拟语气“以言附愿”的微妙性。 关键词：虚拟语气；语气隐喻；人际功能 中图分类号：h08文献标识码：a文章编号：1671―1580（2014）02―0115―02 在英语中，通常用以下三种方式来表现语气的变化：第一，通过不同词汇的选择；第二，通过动词形式的变化；第三，通过语调的变化。在陈述语气和虚拟语气中，动词的形式是不一样的，那么不一样的动词形态在表达的意义上是否有着微妙的变化？陈述语气能否完全取代虚拟语气？ 《大学英语语法手册》第三章《虚拟语气》中有这样的陈述：“正式文体中，在表示建议、命令或请求的动词后，that从句的动词常常用虚拟形式……”此种表述本身是正确的，问题在于例句的选择全部局限在虚拟的用法上，这可能会让初学者误以为虚拟形式的表达是唯一的。《剑桥高级英语语法》对此加以补充说明：在非正式的语言环境中可以用陈述语气替代虚拟语气，例如： （1）i suggest he apply for the job. （subjunctive） （2）i suggest he applies for the job. （indicative） （3）i suggested they drive along the coast. （subjunctive） （4）i suggested they drove along the coast. （indicative） （5）it is important that i study grammar， that you study grammar， and （believe it or not） that she study grammar. （subjunctive） （6）it is important for me＼you＼him to study grammar. （indicative） 以上的例句（2）、例句（4）和例句（6）分别以陈述语气替代了虚拟语气，传达着同样的意义，但是有必要呈现出来让初学者明白，在某种程度上“虚拟”的表达形式并非是“必须”的；只是在一定的语境下，虚拟在表达上更正式一些，在语气上更强烈一些；有时在没有前提语境的情况下，虚拟还是非虚拟是很难区分的： 在此例句中，虽然虚拟和陈述的表达在语言形式上是一样的，但未必表示完全等同的含义，功能语言学认为形式和意义之间并不存在着一对一的关系。陈述语气向虚拟语气的转变与其说是语言形式的变化，不如说是意义上的重大变化。我们把这种语气变异现象，即从一种语气域向另一种语气域的转移，称为语气隐喻。语气隐喻是人际语法隐喻的体现。语言具有表达讲话者态度、动机和对事物判断等功能，按照不同的意愿选择不同的语气就是人际语法隐喻。一种言语功能可以由不同的语气来体现；反之，一种语气也可以体现一种以上的语言功能。 既然虚拟式可以用陈述式来替代，那么是否意味着虚拟的表达形式没有深入探讨的必要呢？有的研究者认为“表面上纷繁复杂的虚拟用法其实完全可以归入陈述语气和祈使语气之下。取消虚拟语气理据充分，有助于结束学界在虚拟语气问题上的尴尬。”基于这种论调，多数人为了规避风险有意绕开虚拟的表达形式从而使得本来就很难运用得当的虚拟语气处于一种临界消失的边缘状态。下面我们从虚拟语气的几种常用表达上阐述虚拟语气与陈述语气的细微差别，从而揭示虚拟语气在表达意义和传递情感上的独到之处。 一、虚拟式表示一种愿望，陈述式表示一种事实 （8）god bless us. （subjunctive） （9）god blesses us.（indicative） 二、虚拟式表示难于或无法实现的愿望，陈述式表示可实现的愿望 （11）i hope she is happy. （indicative） 四、虚拟式表示一种怀疑或无法证实的猜测，陈述式表示有据可依的猜测
英语总复习虚拟语气难点、易错点(1)
英语总复习虚拟语气难点、易错点(1) 一、初中英语虚拟语气 1．If I ____ a candle, I would light the world bright. A．am B．are C．be D．were 【答案】D 【解析】 试题分析：句意：如果我是一根蜡烛，我将点亮这个世界。if I were 如果我是…，were虚拟语气，be动词都用were,故选D 考点：if条件句的虚拟语气 点评：if条件句的虚拟语气，是中考要求掌握的知识点，分为三种情况： 表示与现在事实相反的情况，从句谓语动词用一般过去式（be用were），主句谓语动词用should/would/could/might +do;2.表示与过去的事实相反的情况，从句谓语动词用过去完成时，主句谓语动词用should/would/could/might+have done;3.表将来的事实相反的情况，从句谓语动词用should+动词/did/were to do，主句谓语动词用should/would/could/might +do。 2．If I _____ one million dollars, I________ travel around the world with my parents. A．have; will B．had; will C．had; will D．had; would 【答案】D 【解析】 试题分析：如果我有一百万美元，我要和我的父母环游世界。结合语境可知主句描述的是将来动作，用将来时态。从句中是对将来的虚拟，故用过去时态。选D。 考点：if引导的条件状语从句 点评：虚拟语气是一种特殊的动词形式，用来表示说话人所说的话并不是事实，而是一种假设、愿望、怀疑或推测。其主要有三种结构： 1、与现在事实相反 若与现在事实相反，条件从句的谓语用过去式（be通常用were），主句谓语用“should （would, could, might）+动词原形” 2、与过去事实相反 若与过去事实相反，条件从句的谓语用过去完成时（had+过去分词），主句谓语用“should （would, could, might）+have+过去分词” 3、与将来事实相反 若与将来事实相反，条件从句的谓语用过去式（be通常用were），主句谓语用“should （would, could, might）+动词原形”： 3．_______ in order to sit for the college entrance exam? A．What did she suggest he read B．What did she suggest he reads C．Did she suggest for him to read D．Did she suggest what he read 【答案】A
情态动词与虚拟语气
一．情态动词 1.---Could I borrow your dictionary? ----Yes,of course you_____. A.might B. will C. can D. should 2.---Shall we go skating or stay at home? ----Which _____do yourself? A.do you rather B.would you rather C.will you rather D.should you rather 3.It’s nearly seven o’clock.Jack ___be here at any moment. A. must B need C should D can 4.A computer __think for itself ,it must be told what to do. A. can’t B couldn’t C may not D might 5. Johnny,you ___play with the knife.You ___hurt yourself. A.won’t ;can’t B. mustn’t; may C. shouldn’t; must D. can’t; shouldn’t 6.—Shall I tell John about it? -----No,you _____.I’ve told him already. A. needn’t B.wouldn’t C. mustn’t D. shouldn’t 7.---Don’t forget to come to my birthday party tomorrow. ----______. A.I don’t B.I won’t C.I can’t D.I haven’t 8.He ____you more help,even though he was busy. A.might have given B.might give C.may have given D.may give 9.----There were already five people in the car but they managed to take me as well. ---It ___a comfortbable journey. A.can’t be B.shouldn’t be C.mustn’t have been D.couldn’t have been 10.I told Sally how to get there ,but perhaps I ___for her. A.had to write it out B.must to have written it out C.should have written it out D.ought to write it out 11.---When can I come for photos?I need them tomorrow afternoon. ---They ___be ready by 12:00. A.can B. should C might D need 12.---I stayed at a hotel while in New York. ----Oh,did you?You ____with Barbara. A.could have stayed B.could stay C.would stay D.must have stayed 13.-----Alice, you feed the bird today.____? -----But I fed it yesterday. A.do you B.will you C.didn’t you D.don’t you 14.The fire spread through the hotel very quickly but everyone ____get out. A.had to B.would C.was able to D.could
虚拟语气用法总结及详细解析
虚拟语气用法 英语中的语气分为陈述语气、祈使语气、虚拟语气、疑问语气和感叹语气五类。 1、表示动作或状态是客观存在的、确定的或符合事实的，用于陈述句、疑问句和某些感叹句中。 China is an Asian country. (肯定句) How interesting my stay in China has been! (感叹句) 2、祈使句表示说话人对对方的请求、警告，建议或命令。如: Please come over here. 请到这边来。 Watch your steps! 当心!(走路) 3、虚拟语气表示说话者做出的假设而非事实，或难以实现的情况，甚至表达彻底相反的概念。此外，如需表达主观愿望或某种强烈的感情时，也可用虚拟语气。虚拟语气是由句中的谓语动词的特殊形式表示出来的。如: If I were a bird，I would be able to fly in the air. 如果我是一只小鸟，我就能在空中飞行。 I wish I could pass the examination. 我希望我能通过考试。
If there were a heavy snow next Sunday, we would not go skating. 如果下周日下大雪，我们就不能去滑冰了。 If she were to be here next Monday, I would tell her about the matter. 如果她下周一来这儿的话，我就会告诉她这件事的始末。 4、有时，虚拟条件句中，结果主句和条件从句的谓语动作若不是同时发生时，虚拟语气的形式应作相应的调整。这种条件句叫错综条件句。 ①从句的动作与过去事实相反，而主句的动作与现在或现在正在发生的事实不符。 If I had worked hard at school, I would be an engineer, too.如果我在学校学习刻苦的话，我现在也会成为一个工程师了 If they had informed us, we would not come here now. 如果他们通知过我们的话，我们现在就不会来这里了。 ②从句的动作与现在事实相反，而主句的动作与过去事实不符。 If he were free today, we would have sent him to Beijing. 如果他今天有空的话，我们会已经派他去北京了。 If he knew her, he would have greeted her. 要是他认识她的话，他肯定会去问候她了。 5、当虚拟条件句的谓语动词含有were, should, had时，if可以省略，这时条件从句要用倒装语序，即把were, should, had等词置于句首，这种多用于书面语。 Should he agree to go there, we would send him there.要是他答应去的话，我们就派他去。 Were she here, she would agree with us.如果她在这儿的话，她会同意我们的。 Had he learnt about computers, we would have hired him to work here. 如果他懂一些电脑知识的话，我们已经聘用他来这里工作了。 【注意】 若条件从句为否定句，否定词not应置于主语之后，而不能与were，should，had 等缩略成Weren't，Shouldn't，Hadn't而置于句首。 Had it not been for the bad weather we would have arrived on time. 若不是天气坏，我们就准时到达了。 ②有时省略if后提前的had不是助动词: Had I time，I would come. 假若我有时间，我会来的。(=If I had time…) 6、非真实条件句中的条件从句有时不表达出来，暗含在副词、介词短语、上下文或其他方式表示出来，这种句子叫做含蓄条件句。 ①将条件会暗含在介词短语中，如without…, but for…,otherwise（要不是因为）等 But for his help, we would be working now. (要不是他的帮助，我们还会在工作呢。
高考英语虚拟语气知识点专项训练及答案
高考英语虚拟语气知识点专项训练及答案 一、选择题 1．She wouldn’t have flown off the handle _____the fact that you didn’t intend to hurt her. A．were she to know B．had she known C．did she know D．should she have known 2．-You came second in the running race. Congratulations! -Thanks. But practising more, I _______ a different result. A．might get B．may get C．may have got D．might have got 3．You can download it and rewrite your report using your own words you acknowledge where you got your information by attaching a list of websites you got your information from. A．should B．may C．would D．could 4．Recent years have seen a growing increase in the emergence of cyber terms, without which our life _____ so colorful nowadays. A．won’t be B．hadn’t been C．wouldn’t be D．can’t be 5．With the help of the detective Sam, Justin was found, so Justin's mother insisted an amount of money as a reward. A．to give B．on his giving C．he was given D．he be given 6．—Where are the children? The dinner’s going to be complerely ruined. —I wish they always late. A．weren’t B．hadn’t been C．wouldn’t be D．wouldn’t have been 7．That was not the first time he ____ us. I think it's high time we ____ strong actions against him. A．betrayed, take B．had betrayed, took C．has betrayed, took D．has betrayed, take 8．It is recommended that the project ______ until all the preparations have been made. A．is not started B．will not be started C．not be started D．is not to be started 9．Studies show that historical barriers on women acceptance in organizational environments, the development of the company would already be way ahead. A．were it not for B．if there being no C．hadn't it been for D．if it is not for 10．--- Are you happy now? --- If only I _____ slimmer, more beautiful, richer, more clever. A．am B．were C．had been D．should be 11．What a pity! Considering his ability and experience, he ___________ it better. A．need have done B．must have done C．can have done D．might have done 12．_____, the student insisted that he _____ separated from his desk mate, who is very naughty. A．To avoid being affected; be B．To avoid to be affected; would be
情态动词和虚拟语气
情态动词和虚拟语气 情态动词的用法要点 一、表能力 Can Am/is/are able to 表现在的能力 Will be able to 表将来的能力 could Was/were able to 表过去得能力 Could have+过去分词：表示过去有能力做但未做 二、表推测（可能性） 1.可能性可分为客观的可能性和具体事情实际发生的可能性两种。所谓客观的（理论的）可能性即并不涉及 具体某事是否会发生，此种用法常常可以说明人或事物的特征。情态动词can可用于肯定句中表示客观的（理论的）可能性，而表示具体事情实际发生的可能性时，can一般不用于肯定句。 Accidents can happen on such rainy days. We may go to the cinema tonight, but we are not sure yet. 2.表示具体事情实际发生的可能性： （2）表示具体事情实际发生的可能性时，may, must 常用于肯定句，一般不用于否定句和疑问句（may not 表示“可能不”）；can常用于否定句、疑问句或感叹句中，表示疑惑、惊讶或不相信等意思；could既可用于肯定句又可用于否定句、疑问句中。 This can’t/ couldn’t be done by him. This may not be done by him. He could be on his way home now. Can this be done by him? Mr Mush is on time for everything. How can it be that he was late for the opening ceremony? I didn’t hear the phone. I must have been asleep. ---Are you coming to Jeff’party? ---I’m not sure. I might go to the concert instead. (3) would, could, should, might 并不一定与过去时间有关，而表示可能性弱于它们相应的现在时形式。 This may/ might be done by him. (4)should 表推测时，表示确定或可能有的未来或期望，即合乎理想的情况或结果 He ought to/ should be here on time---he started early enough. We should arrive before dark. The roads should be less crowded today. 三、表示请求、允许、允诺 1.当对方是决策者时，你代表你（们）自己（I, we），或代表第三者（he she they）向对方（you）请示或提 出建议时用：
虚拟语气的构成及其用法
语气 (mood)是一种动词形式，用以表示说话者的意图或态度。英语中的语气有三种：陈述语气、祈使语气和虚拟语气。 直陈语气(indicative mood),表示所说的话是事实。 祈使语气 (imperative mood),表示所说的话是请求或命令。 虚拟语气(subjunctive mood),表示说的话不是事实，或者是不可能发生的情况，而是一种愿望、建议或与事实相反的假设等。 一. 虚拟语气在条件句中的应用 学习虚拟语气在条件句中的用法之前我们必须清楚条件句的种类：条件句有真实条件句与非真实条件句(或称虚拟条件句)两种。真实条件句所表的假设是可能发生或实现的，句中的条件从句与结果主句都用陈述语气。 如： If it doesn’t rain tomorrow, I will go for a picnic. 假若明天不下雨，我就去野餐。 Oil floats if you pour it on water. 你如把油倒在水里，油就浮起来。 虚拟条件句所表的假设则是不可能或不大可能发生或实现的，句中的条件从句与结果主句皆须用虚拟语气。 1. 与现在事实相反的虚拟条件句，条件从句的谓语用动词的过去式 (be的过去式用were), 主句的谓语用should （would, might，could）+动词原形。 如： If it were not raining, we should go for a picnic.如果现在不下雨的话，我们就出去野餐了。 （事实是：天在下雨，我们不能出去野餐。表示愿望。） If he came here, he might be able to help you. 如果他来这，他就能够帮助你了。 （事实是：他没来这，他不可能帮助你。表示对他的良好印象。） 2. 与过去事实相反的虚拟条件句，条件从句的谓语用had+过去分词，主句的谓语用should （ would, might， could）+ have ＋过去分词。
高考英语语法难点：虚拟语气
虚拟语气(the subjunctive mood,又称假设语气,是谓语动词的一种形式,表示说话人叙述的内容与事实相反,在现实中并不存在,或实现的可能性很小。 一、动词的语气 语气用来区别讲话人对某一行为或事情的看法和态度。英语中的语气(mood有三种,分别是陈述语气、祈使语气和虚拟语气。 1.陈述语气 陈述语气一般用来叙述事实或就事实提出询问,主要用于陈述句、疑问句和某些感叹句。 Where there is a will, there's a way. 有志者事竟成。 Can you help me carry the box upstairs 你能帮我把箱子搬到楼上吗? How I missed the life in the countryside! 我多么想念乡村的生活啊! 2.祈使语气 祈使语气表示说话人向对方提出请求或下达命令。 Come this way,please! 请这边走。 Don't make any noise, will you 别吵,行吗? Do be careful when crossing the street. 过马路时一定要小心。 3.虚拟语气 虚拟语气表示动作或状态不是客观存在的事实,而是说话人的主观愿望、假设或推测等。 If I were a bird, I could fly in the air. 如果我是一只小鸟,我就能在空中飞行。 I wish it were spring all the year round. 但愿四季如春。 May good luck be yours! 祝你好运! 二、条件句中的虚拟语气 英语中条件从句有两类,一类是真实条件句,另一类是非真实条件句。如果假设的情况可能发生,是真实条件句;如果假设的情况是不存在的或不大可能发生的,则是虚拟条件句。 A.真实条件句 真实条件句表示的假设是可能发生或实现的,主句和从句的谓语动词都要用陈述语气。 If he doesn't come at 8, we won't wait for him. 如果他八点不来,我们就不等他了。 If a flood happened in the past, there was usually a great loss of life and property.过去发生洪水的话,常有很大的生命和财产损失。 We shall go there unless it rains tomorrow. 如果明天不下雨,我们将去那里。 I'll let you use my bike on condition that you keep it clean. 如果你能保持车子干净,我就让你用我的自行车。 B.非真实条件句 在含有非真实条件句的复合句中,主句和从句的谓语动词都要用虚拟语气,其构成有三种形式: 与现在事实相反if条件句的谓语:were did