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虚拟语气归纳和练习

录入者:netlab  人气指数: 次  发布时间:2010年01月28日

虚拟语气归纳和练习  

 

虚拟语气的重点是:
1
.一些常见的虚拟语气的句型或结构。
2
.虚拟语气的特殊形式,即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式。
3
.主从句表示不同的时间概念、事实或假设情况,从而交错成为复合虚拟语气。
4
.含蓄条件句中的虚拟语气的表示愿望的虚拟形式。
上述四个要点往往在完形填空或者阅读理解里面存在,尤其是每年完形填空都至少有一道直接考这方面的知识的题目,而在阅读理解里,我们掌握上述四个重点对于我们理解文章的大意和作者态度很有帮助,了解哪些观点是作者假设的、虚拟的,哪些是真实的,这样对于我们回答关于作者态度观点题很有帮助。
下面我们将主要从上述四个方面来重点论述在考试中应该注意的问题。
一、虚拟语气的常见类型和句型
1)由wish引起的表示愿望的虚拟语气
A
.用wish表示对现在的愿望时,它所引起的宾语从句中谓语动词形式为:过去式(be动词用were)。
B
.用wish表示对将来的愿望时,它所引起的宾语从句中谓语动词形式为:would, could, might+ 动词原形。
C
wish用于对过去的事实表示一种不可能实现的愿望时,宾语从句中的谓语动词形式为:had+动词过去分词或could, would + have +动词过去分词。
The picture exhibition bored me to death; I wish I had not gone to it.
---“I let Joe borrow our radio for the afternoon.”
---“That’s all right, but I wish he would buy one of his own.”
I wish that he weren’t so lazy.
(2)had hoped
引起的宾语从句中备用语动词形式为would+动词原形,表示一种过去未实现的愿望或令人失望的事。
His father had hoped that his son would go to business with him, but his son became an artist later.
(3)would (had) rather, would as soon, would sooner
would prefer所引起的从句中要求用过去式表示当时或将来的情况,用过去完成时表示过去的情况,表示希望或婉转的责备。例如:
I’d rather you posted the letter right away.
我倒希望你把这封信立刻寄出去。
I would prefer he didn’t stay there too long.
我倒希望他不要在那儿可得太久。
I would just as soon you had returned the book yesterday.
我真希望你昨天把这本书还了。
4It’s (high, about) time that 句型中that从句中要求用虚拟语气形式,即动词要用过去式。
It’s time that something was done about the traffic problem downtown.
It is high time that we put an end to this discussion.
现在是我们该结束讲座的时候了。
5as, 或者whether…or…谓语多用be的原形,引导让步虚拟从句,这种用法通常采用倒装结构:
Church as we use the word refers to all religious institutions, be they Christian, Islamivc, Buddhist, Jewish, and so on.
The business of each day, be it selling goods or shipping them, went quite smoothly.
6)由连接词in case, so that ,unless, lest ,for fear that引起的状语从句中,谓语动词要用虚拟形式,即should(might, would)+动词原形,例如:
She put a blanket over the baby for fear that he should catch cold.
她在那个婴儿身上盖上了毯子以免他着凉。
The bad man was put in the soft-padded cell lest he injure himself.
(7) if it were not for…
与现在事实相反, if it had not been for与过去事实相反,两个都相当于but for
If it had not been for his help(=but for his help),we would not have succeeded.
(8)
虚拟语气用于as ifthough)引起的方式状语从句和表语从句中,其动词形式与wish宾语从句的形式相同。例如:She often laughs spontaneously, and her good humor breaks out as brightly as if it were a part of the sunshine above.她常常发出发自内心的微笑,而且她那美好的情绪像天上一道明亮的阳光一样,常常流露出来。
They talked as if they had been friends for years.
他们交谈着,就好像他们是我年的老朋友一样。
She looks as if she would cry.
她看起来好像要哭了。
(9)
其它各种句型, as though, suppose, had rather, supposing, if only等等
If I were in a movie, then it would be about time that I buried my head in my hands for a cry.
二、特殊形式的虚拟语气
虚拟语气的特殊形式,即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式,其虚拟语气的构成往往是由should(可省略)+动词原形that从句。
A
、 用于表示意愿、建议、命令、提议、请求等动词后的that宾语从句中,这类动词有:
ask
要求 advise建议 arrange安排 beg请求
command
命令 decide决定 demand要求 desire渴望
determine
决定 insist坚持 intend打算 maintain坚持主张
move
建议,动员 propose提议 object反对 order命令
prefer
建议 require 需要 request要求 resolve下决心
recommend
推荐 suggest建议 stipulate约定,规定 urge强调,促进
vote
公认,提议 decree颁布(法令) pray请求
注意:这类动词后面除了可接that虚拟句以外,也可以接doing或者to do…来表达,一般情况下,意思没有什么差别。
She advised that we should keep the gate locked.
(书面体)
She advised us to keep the gate locked.
(口语)
She advised keeping the gate locked.(
较随便)
B
、用于It is+形容词或过去分词+主语从句中,这类形容词或分词有:
advisable
合理的 decided决定的 crucial关键的 appropriate恰当的
determined
决定的 commanded命令的 arranged安排的 essential紧要的,基本的
complied
遵照 anxious焦急的 imperative迫切的 important重要的
desirable
合意的 better较好的,更好 insistent坚持的 desired想要
asked
请求 keen渴望的 incredible难以置信的 adamant坚定不移的
natural
自然的 insisted坚持 necessary必要的 suggested建议
urgent
紧迫的 ordered命令 shocked震惊的 vital极其重要的
possible
可能的 strange 奇怪的 preferable (好一点) proposed提议
requested
要求的 required要求的 recommended推荐 resolved决定的
probable
(可能的) pity可惜,憾事 shame遗憾
注意:这类形容词后面除了可接that虚拟句以外,也可以for…to do…
来表达,一般情况下,意思没有什么差别。
It is essential that he should be prepared for this.
It is essential for him to be prepared for this.
C
.用于由表示建议、要求、命令、请示等含义的名词引导的表语从句和同位语从句中,这类名词常见的有:
advice
忠告 decision决定 demand要求 desire要求、愿望
insistence
坚持 motion提议 necessity必要性 order命令
preference
偏爱 proposal提议 pray恳求 recommendation推荐
request
要求 requirement要求 resolution决心 suggestion劝告、忠告
例如:
This is their resolution that extra-curriculum activities be made part of their school life.
这是他们的决议:要使得课外活动成为他们学校生活的一部分。
The motion that the remark of the last speaker be expunged from the record.
该提议要求把最后一个发言的人的讲话从记录上除掉。
三、混合虚拟语气
有时主句和从句的谓语动词指不同的时间,这时需要用混合虚拟语气。一般来说,在这种情况下,主从句谓语动词指代的时间不同,所以我们又可以错综时间条件句,在这种虚拟情况,动词形式应根据实际情况灵活使用,在做这些题目时候尤其要注意每道题目的提示语:时间状语。绝大多数情况下,从句或者主句都有相关的时间状语,这是我解题的关键。
If you that late movie last night, you wouldn’t be so sleepy.
A. haven’t watched B. didn’t watch
C. hadn’t watched D. wouldn’t have watched
答案选C
Many dead would now be alive if they have not attempted to return for something.
Had Paul received six more votes in the last election, he would be our chairman now.
混合虚拟语气还有一种情况就是事实和虚拟假设的混合句,这样的句子不仅仅是时间的不同,而重要是事实和假设的混合。
I would have gone to visit him in the hospital had it been at all possible, but I was fully occupied the whole of last week.
该句前半部分是假设虚拟,而后半部分是事实的陈述。
Your math instructor would have been happy to give you a make-up examination had you gone and explained that your parents were ill at the time.
该句前半句用的是假设虚拟,后半句主句也用的是假设虚拟(如果你去并且解释的话),但是后半句的从句用的是事实语气,因为父母病了是客观事实,故不需要用虚拟形式had been
四、含蓄虚拟条件句
含蓄条件句是指句中没有明显的虚拟条件句,而是利用其他手段来暗示存在虚拟条件。但是这类隐含式虚拟条件句往往都可以转化为if引导的条件句。常来表示含蓄虚拟条件的手段有:
1)介词或介词短语,如but for, but that, without, in case of, under more favorable condition等。
the leadership of the party, we could not be living a happy today.=If there hadn’t been the leadership of the party, we could not be living a happy today.
A. In spite of B. But for C. Because of D. As for
答案选B
But that she was afraid, she would have said no.
(2)
连词,如:so that, unless, in case, supposing, lest, provided(倘若……)for fear that(唯恐)in order that, on condition that, if only(要是……就好了)等。
She listened carefully in order that she might discover exactly what he wanted.=if she listened carefully ,she might discover exactly what he wanted.
If only I had more money, I could buy a car.
(
注:lest, for fear that in case 引起的从句中谓语动词多用should+动词原形,但可以不用虚拟语气,而用动词的陈述语气形式。)例如:
The foreign teacher spoke slowly in case we misunderstood him.
这位外籍教师说得很慢以免我们听不懂。
Care must be taken in using this method lest overflow should occur.
在使用此法时要小心谨慎,以免会发生溢流现象。
3)通过上下文及内在含义,句中往往有but, otherwise, unfortunately等类似转折词。
I thought the children when we returned home, but they were still awake.
A. were sleeping B. would be sleeping C. had been sleeping D. would sleep
选择 B
(4)
形容词及其比较级
A more careful person would not have made so many mistakes.
A less conscientious man wouldn’t have tried so hard to get this job done.
(5)
分词短语
Having known in time, we might have prevented the accident.
Born ten days earlier, the boy could have seen his late father.
(6)
动词不定式短语。一般intended/meant/hoped/wished/planned was/were+不定式完成式或had intended/meant/planned/hoped/wished/+不定式一般式表示虚拟。
I intended I should call on you, but I was busy at that time.
To hear him speak French, you would take him for an Englishman.
She would be stupid not to accept his invitation.
It would be easier to do it this way.
(7)
名词短语和名词+and结构
A judicious man would not have committed suicide.
A diligent student would have worked harder.
(8)
独立主格结构
All things considered, the price would be reasonable.
(9)
定语从句
Anyone who had been in your position would have done the same.
A nation, which stopped working, would be dead in a fortnight.
(10
)情态动词完成式暗示虚拟语气:
I should have called to make an airline reservation, but I didn’t.
The porter ought to have called the fire-brigade as soon as he saw the fire in the stock, which went up in smoke.
(11)
动词原形表示虚拟
动词原形直接用在句子中也被看作是一种虚拟,最常见于正式文体中,动词原形一般用在条件从句中,有时倒装置于句首,同时这种用法也常见于独立句中表达愿望。
God bless you!
All magnets behave the same, be they large or small.
She’ll be sixteen years odd, com May.(come May =when May come).
If that be so, we shall take action at once.

强化训练:虚拟语气
1
Were it not for the snowy weather, we all right.
A. would be B. would have been C. were D. may be
2. more careful, his ship would not have sunk.
A. If the captain were B. Had the captain been
C. Should the captain be D. If the captain would have been
3. If he me tomorrow, I would let him know.
A. should call B. should not have been able
C. were not able D. are not able
4. If you asked your father you permission.
A. may get B. might get C. should have called D. maybe get
5. today, he would get there by Friday.
A. Would he leave B. Was he leaving C. Were he to leave D. If he leaves
6. ______I you, I would go with him to the party.
A. Was B. Had been C. Will be D. Were
7.The millions of calculations involved, had they been done by hand, ______all practical value by the time they were finished.
A. could lose B. would have lost C. might lose D. ought to have lost
8. Had Paul received six more votes in the last election, he our chairman now.
A. must have been B. would have been C. were D. would be
9. If you Jerry Brown until recently, you’d think the photograph on the right was strange.
A. shouldn’t contact B. didn’t contact C. weren’t to contact D. hadn’t contacted
10. he English examination I would have gone to the concert last Sunday
A. In spite of B. But for C. Because of D. As for
11. Look at the terrible situation I am in! If only I your advice
A. follow B. would follow C. had followed D. have followed
12. Had Paul received six more votes in the last election, he our chairman now.
A. must have been B. would have been C. were D. hadn’t contacted
13. If the horse won today, it thirty races in five years.
A. would have won B. won C. must have won D. did have won
14. There is a real possibility that these animals could be frightened, _______a sudden loud noise.
A. being there B. should there be C. there was D. there having been
15. The board deemed it urgent that these files right away.
A. had to be printed B. should have been printed
C. must be printed D. should be printed
16. Jean Wagner’s most enduring contribution to the study of Afro-American poetry is his
insistence that it in a religious, as well as worldly, frame of reference.
A. is to be analyzed B. has been analyzed
C. be analyzed D. should have been analyzed
17. I would have gone to visit him in the hospital had it been at all possible, but I ______
fully occupied the whole of last week.
A. were B. had been C. have been D. was
18. I apologize if I you, but I assure you it was unintentional.
A. offend B. had offended C. should have offended D. might have offended
19. If you hadn’t taken such a long time to get dressed, we’d there by now.
A. be B. circles C. is circling D. be circling
20. The sun rises in the east and sets in the west, so it seems as if the sun ________round the earth.
A. were circling B. circles C. is circling D. be circling
21. I wish that I ______ with you last night.
A. went B. have gone C. could go D. could have gone
22. I wish I with her.
A. would be B. am C. was D. were
23. I wish that I the concert last night.
A. could B. have attended C. could have attended D. attended
24. The picture exhibition bored me to death. I wish I to it.
A. had not gone B. have not gone C. did not go D. can not have gone
25. “I wish you me to put these things away,” he said.
A. will help B. help C. are helping D. would help
26. If the Watergate Incident Nixon would not have resigned from the presidency.
A. did not occur B. had not occurred C. was not occurring D. be circling
27. I hadn’t expected James to apologize but I had hoped .
A. him calling me B. that he would call me C. him to call me D. that he call me
28. George would certainly have attended the proceedings .
A. if he didn’t get a flat tire B. if the flat tire hadn’t happened
C. had he not had a flat tire D. had the tire not flattened itself
29. The teacher suggested that her students experiences with ESP.
A. write a composition on their B. to write composition about the
C. wrote some compositions of his or her D. had written any compositions for his
30. He speaks Chinese as fluently as if he ______a Chinese.
A. were B. had been C. is D. has been
31. As usual, he put on a show as though his trip a great success.
A. had been B. has been C. were D. was
32. Looking round the town, he felt as though he away for ages.
A. has been B. was C. is D. had been
33. John is so strongly built that he looks as if he as elephant.
A. lifts B. is lifting C. lifted D. could lift
34. He described the town as if he it himself.
A. had seen B. has seen C. saw D. sees
35. At that thought he shook himself, as though he from an evil dream.
A. woke B. wakes C. would wake D. had woke
36. Most insurance agents would rather you anything about collecting claims until
they investigate the situation.
A. do B. don’t C. didn’t D. didn’t do
37. Although most adopted persons want the right to know who their natural parents are, some who have found them wish that they the experience of meeting.
A. hadn’t B. didn’t have had C. hadn’t had D. hadn’t have
38. It is important that the TOEFL office your registration.
A. will confirm B. confirm C. confirms D. must confirm
39. Without electronic computers, much of today’s advanced technology .
A. will not have been achieved B. have not been achieved
C. would not have been achieved D. had not been achieved
40. He told her to return the book in time so that others a chance to read it .
A. may have B. will have C. would have D. might have
41. It is time that the government measures to protect the rare birds and animals.
A. takes B. took C. has taken D. taking
42. Some people are too particular about school records, insisting that every applicant ______all diplomas from elementary school to university.
A. has B. will have C. should have D. must have
43. He was very busy yesterday, otherwise he to the meeting.
A. would come B. came C. would have come D. had come
44. I must say he reads very well, and I shouldn’t be surprised if he acting for a living one day.
A. had taken up B. takes up C. have taken up D. would have taken up
45. If I had seen the movie, I you all about it now.
A. would tell B. will tell C. have told D. would have told
46. I hadn’t expected Henry to apologize but I had hoped .
A. him t call me up B. him calling me up
C. that he would call me up D. that he will call me
47. I had hoped that John ______a year in Africa, but he stayed there only for three months.
A. spends B. spent C. would spend D. will spend
48. I had hoped that Jennifer a doctor, but she wasn’t good enough at science.
A. will become B. became C. would become D. becomes
49. I’d rather you anything about it for the time being.
A. do B. didn’t do C. don’t D. didn’t
50. I’d just as soon_______ rudely to her.
A. that you won’t speak B. you not speaking
C. you not speak D. you didn’t speak
51. It’s high time they this road.
A. mend B. mended C. must have mended D. will mend
52. It’s about time people______ notice of what women did during the war.
A. take B. took C. have taken D. will take
53. Everybody has arrived. It’s time we the class.
A. shall start B. would start C. had started D. start
54. the English examination I would have gone to the concert last Sunday.
A. In spite of B. But for C. Because of D. As for
55. Mary my letter; otherwise she would have replied before now.
A. has received B. ought to have received
C. couldn’t have received D. shouldn’t have received
56. John did not feel well yesterday; otherwise he _______to see his classmates off.
A. came B. would come C. would have come D. should be coming
57. He’s working hard for fear that he .
A. should fall behind B. fell behind C. may fall behind D. would fall behind
58. Without the dreams of the youth, this invention might for a century.
A. have been postponed B. has been postponed
C. postpone D. be postponed
59. In the past men generally preferred that their wives______ in the home.
A. worked B. would work C. work D. were working
60. For a child to give up his less mature idea for a more mature one, it requires that the child
psychologically ready for the new idea.
A. is B. were C. be D. would be
61. Tom’s father, as well as his mother, in New York for a few days more.
A. ask him to stay B. ask he to stay C. asks he stays D. asks he stay
62. Your advice that______ till next week is reasonable.
A. she waits B. she wait C. wait she D. she waited
63. The board deemed it urgent that these files right away.
A. had to be printed B. should have been printed
C. must be printed D. should be printed
64. It was essential that we lease before the end of the month.
A. sing B. singed C. had signed D. were signing
65. It is appropriate that some time ______thorough study of the results of the Apollo mission.
A. devotes to B. devoted to C. is devoted to D. be devoted to

答案与详解
1
A.条件句表示与现在事实相反的虚拟。
2
B.条件句表示与过去事实的虚拟。
3
A.条件句表示与未来事实的虚拟。
4
B.条件句表示与未来事实的相反。
5
C.条件句表示与现在事实的虚拟。
6
D.条件句表示与现在事实的虚拟。
7
B.这个句子中含有一个省略if,把助动词提前到主语they之前的虚拟条件句,该条件句表示对过去情况的假设,而主句中by the time they were finished 表明主句也应该是对过去发生的情况的假设,因而应该选(Bwould have lost为正确答案。
8
.(D)这道题目是一个混合虚拟语气的句子。条件句省略了if,把助词had提前到主语前面,表示对过去情况的假设,而主句中now表明了对现在情况的假设,所以应选would(should, could, might)+动词原形这种表达形式。四个选项中只有(D)是正确表达形式,故为正确答案。
9
.(Duntil recently,因此(D)是正确答案,而主句是隐含的对现在情况的假设,该句是一个混合虚拟条件句。
10
.(B)假设的情况有时不是用一个条件句表示,而是隐含在一个由介词如but forbut thatwithout, 由连词but、副词otherwise 、比较级、形容词、独立主格等表示的上下文中。本句主句表示对过去情况的假设,但事实上由于英语考试而没有去成,即若不是因为英语考试,我本可以去听音乐会,所以应选But for为正确答案。
11
.(C)题目中的第一句话表示的是现在真实的情况,而第二句话中所要表达的是应该做但事实上没有做的事,这种情况导致第一句话中真实情况的发生,故If only条件句假设的是过去一种情况,因此应该用had +过去分词,所以正确答案是(C)。
12
D.注意主句now表示现在的时间状语,所以主句是对现在虚拟,从句是对过去虚拟。
13
A.从句对过去的虚拟。
14
B.从句表示虚拟,而主句是事实。
15
.(Dit是形式宾语,urgent是宾语补足语,that引导的从句是真正的宾语从句,该从句的内容被认为是urgent(急迫的),这样从句的谓语动词要求用虚拟语气形式,即should(可以省略)+动词原形。因此,本题正确答案是(D)。
16
.(C)在表示要求、愿望、建议、请求、命令等含义的名词同位语从句中,从句谓语动词要用虚拟语气形式,即should(可以省略)+动词原形。
17
.(D)本道题目的前半句话是对过去情况的一种假设,但事实上并没有发生,而事实上没有发生的真实原因是句子的后半部分由but引导的转折句所表述的真实。因而but所引导的句子中应该用表示志过去事实相符合的表陈述的时态,即一般过去时。
18
.(B)此题要求在if从句中选择适当的动词形式,以主句中的动词apologize(抱歉)来看,if从句中表达的内容应该是过去做的事,因此可以排除(A),因为(A)是现在时。(C)中should+have+过去分词结构表示本来应该做却没有做的事,在此不合题意。(D)选项中的might+have+过去分词表示对过去发生的事情很不肯定的猜测,它表达的内容还不能成为事实,所以藉此道歉真是不知从何说起,因此此处也不合题意。(Bhad offended表示当时已经发生了的动作。这是复杂条件句:apologize 是现在,而条件句是表示对过去假设的条件句。
19
.(A)该句也是一个复杂条件句(或称作混合虚拟条件句)。条件句表示对过去情况的假设,而主句表示对现在情况的假设,但事实上却与此相反,所以正确答案应该是(A)。
20
.(Aas if引导的从句要求用虚拟语气,表示同时或将来的情况,动词要用过去式(be动词用were)或would(could)+动词原形,本句话中指的是当时的情况,所以要用过去式,故(A)是正确答案。
21
D
22
D
23
C
24
A
25
D
26
.(Bhad not occurred表示对过去的虚拟,条件句中要用过去完成式,主句中要用should(would, could, might)+动词原形的过去分词。
27
.(Bhad hoped是常见的要求其后的宾语从句用虚拟语气的句型,虚拟语气would+动词原形。
28
.(C)表示对过去情况的假设,主句动词形式为would(should, could, might)+have+过去分词,条件句为过去完成式,if可以省略,但要把had提前主语前面。(B),(D)的表达不符合英语表达习惯,所以(C)是正确答案。
29
.(Asuggest后面的从句要用虚拟语气形式,其形式为should(可以省略)+动词原形。
30
A.表示与现在相反的虚拟。
31
Aas though引导的与过去相反的虚拟。
32
Dfelt是过去式,所以该句是由as though引导的与过去相反的虚拟。
33
Das if引导的与现在事实相反的虚拟。
34
Aas if引导的与过去相反的虚拟。
35
C
36
.(Dwould rather后接从句要求用虚拟语气,形式为过去式,表示对现在或将来的假设,或为过去完成式表示对过去的情况的假设。
37
.(Cwho引导的定语从句中的现在完成时表示动作业已发生,所以主句中表示的虚拟是针对已经发生了的行为,所以应该用过去完成式表示对过去的虚拟。
38
.(B
39
.(C)这是一人含蓄虚拟条件句,通过介词短语without,表示潜在的一种假设,而主句中的情况也早已经发生,所以是对过去情况的一种假设,因此用would not have been achieved这一形式。
40
.(D)连so that引导的从句中要求用虚拟语气,表示一种假设,形式为might+动词原形。
41
.(BIt is time that是一种要求从句用虚拟语气的常见句型。虚拟语气形式为动词的过去式。
42
.(C
43
.(Cotherwise用来表示一种含蓄的虚拟假设,因为是对过去(yesterday)的情况的假设,所以应该用would have come形式。
44
.(B)所给的四个选项中没有一个表示对未来的情况的虚拟的形式should+动词原形,或是were to do,因此可以断定if引导的条件句在这里最真实的条件句,用一般现在时表示一般将来时,故(B)是正确答案。
45
.(A)这是一个混合虚拟语气的句子,if条件句表示的是对过去情况的假设,而主句是对现在(now)的情况的假设,故用would tell形式。
46
C
47
C
48
C
49
Bwould rather引导的虚拟语气其谓语用过去式。
50
Dwould as soon引导的虚拟语气,其谓语动词也用过去式.
51
B
52
B
53
B
54
B
55
C.注意单词otherwise引导虚拟语气。
56
C.同上。
57
A.注意词组for fear that
58
A.注意without
59
C
60
C
61
D
62
B
63
D
64
A
65
D  

 

浅谈虚拟语气的几种用法
1
.错综时间条件句
虚拟语气通常用于含条件状语从句的主从复合句中。条件状语从句中表示与现在、过去或将来事实相反的虚拟语气比较容易掌握,但绝不可把它们当作一成不变的数学公式一样对待。就是说,不能只单纯背语法条条框框,而应充分理解句子锁定的语言环境。有时从句动作与主句动作发生的时间不一致。这时就要根据各自表示的时间概念加以调整。如:   

If he had taken my advice, he would be much better
now
.(从句与过去事实相反,主句与现在事实相反。)

2
.含蓄条件句

有时假设的情况并不是以条件状语从句的形式表示出来,而是通过一个介词(如:
without;
butfor)
引出的短语,一个连词(如:but; or; otherwise)引出的从句或其它方式来表示。如:

Without your help, we couldn
t have finished the job in
time
(Without your helpIf you hadnt helped us)

He could have given you more help, but he was busy
(but
he was busy
if he had not been busy)

3
.倒装句

如从句中有were, hadshould,则可以省去if, 并将
were,
had
should提前到句首,构成部分倒装。如:

Were I to be young again, I would study
medicine
(从句正常语序为:If I were to be young again)

Had you not left so early, you might have missed the
train
(从句正常语序为:If you had not left so early)

4
.错综语气

有时从句用虚拟语气,主句却用陈述语气或祈使语气。如:

If there should be an earthquake, what will you
do
﹖(从句用虚拟语气,主句用陈述语气。)

Ask her to leave a message if she should
come
.(从句用虚拟语气,主句用祈使语气。)

5
It is (high) time (that)句型

这个句型往往用“过去时”形式表示“现在”的动作,有时也用“should+动词原形”。如:

It
s high time (that) we began to work

I think it
s time (that) you made up
should make up your
mind

6
.主句中含有
suggest, suggestion, propose, proposal, insist,
order, demand, request
等词时,从句谓语部分常用“(should)+动词原形”。如:

She suggests that they (should) go there right away

Her suggestion is that they (should) go there right
away

It is suggested that they (should) go there right away

7
so that
in order
that
引导的目的状语从句常由“cancouldmaymight+动词原形”构成;在否定结构中,常由“shouldnt+动词原形”构成从句的谓语形式。如:   

Speak clearly so that they maymight understand you
He took a taxi to the station inorder that he should not
miss the train

8
would rather后的宾语从句

表示现在和将来的时间概念时,从句动词用过去式,表示过去的时间概念时,从句动词用“had+过去分词”。如:

I
d rather you came here this Saturday

I
d rather I had seen the professor yesterday