第1个回答 2023-02-21
摘 要：条件式虚拟语气是虚拟语气的基本形式，也是学习虚拟语气的入口，但其各种变体结构多样，不易掌握。本文阐释了条件式虚拟语气及其变体并再现了它们在试题中的应用，以期有效地服务于英语教学和考试。
关键词：虚拟语气 if从句 条件变体
英语语法学习的难点在动词，动词的难点之一是语气，语气难在“虚拟”。虚拟语气主要用来表示与事实相反的主观假设或难以实现的主观愿望，这一功能的实现依赖于谓语部分动词形式的变化。在虚拟语气的各种形式中，条件式结构较固定、趋于公式化，易于学习，但其各种变体结构多变、形式多样，考试常考，学生常错。“常考”只因虚拟在人们生活中必不可少，“常错”只缘不识变体真面目。
一、条件式虚拟语气的构成及类别
条件式虚拟语气由if引导的非真实性条件从句即虚拟条件句加上主句构成，为了表达虚拟含义，从句和主句谓语部分的动词形式都要作相对固定的变化。由于人们面对的时段只有三个：现在、过去和将来，因此，条件式虚拟语气也相应地分为三种类型，构成如下：
示例：
（1）If I had the chance, I would have a sleepless night.
如果我有这个机会，我会失眠。（事实是，我没这样的机会。）
If I were you, I would give it up.
如果我是你的话，我会放弃。（事实是，我不是你。）
（2）If I had seen you in the street yesterday, I would have said “hello” to you.
如果我昨天在街上看到你的话，我当然要打招呼。（事实是，我没看到你。）
If they had known the truth at that time, they would have fought with each other.
如果他们当时了解真相，就会打起来。（事实是，幸亏他们当时不了解真相。）
（3）If I got/should/were to get the information tomorrow, I should let you know first.
如果我明天能得到消息的话，我会第一个让你知道。（事实是，我不大可能得到消息。）
If the earth stopped/ should/were to stop spinning tomorrow, what would happen?
如果明天地球停止转动，那会发生什么情况？（事实是，明天地球不会停止转动。）
二、条件式虚拟语气的各种变体
1.倒装式。如果条件从句谓语部分含有should，were或had，常省略if，并将should，were或had提至句首引起倒装。如：
Should it rain (If it should rain), we could not go out for camping.
Were I in his place (If I were in his place),I might think differently.
Had he recognized me (If he had recognized me), he would have come over.
2. 替代式。有时虚拟条件句不用if从句表示，而是通过介词、介词短语、不定式短语、动名词短语、抽象名词、并列句或上下文等形式表示出来，这种情况也称含蓄条件句。这类词语常见的有with, without, but, but for, but that, given more time, given that, or, or else, otherwise, unless, supposing等。如：
With your help (=if you had helped me), I might have done it better.
Without electricity (=if there were no electricity), human life would be quite different today.
He would have helped me, but he was so lazy (=if he had not been so lazy).
But for the storm (=if it had not been for the storm), we should have arrived earlier.
I’m really busy,otherwise (=if I were not so busy) I would go with you.
Meeting anywhere else (=if we had met anywhere else ), we wouldn’t have recognized each other.
Given more time (=if we had been given more time), we would have done it even better.
To hear him talk (=if you should hear him talk), you’d think he were Prime Minister.
One step further (=if you took one step further) and you would be dead.
Your reputation would be ruined.(虚拟条件暗含在上下文中，可能暗含if you should accept it.)
3. 混合式。有时虚拟条件从句与主句的动作发生在不同的时间，这时从句与主句谓语动词的虚拟语气形式因时间不同而不同，这种情况也称错综时间条件句。做这种类型的练习时，要摆脱基本形式（表格）中公式化思维定势的干扰。如：
If I had worked harder before, I would not worry about my exam now.
If you had asked him yesterday, you would know what to do now.
If he had taken my advice,he would not be in such a position now.
4. 强化式。这里是指用if only代替if, 表示说话人的一种与现在事实、既成事实或将来的事实相反的强烈愿望或遗憾，相应的谓语动词分别用过去时、过去完成时及would/could+动词原形，一般译为“要是”或“只要”。如：
If only he were not so timid, he would be more attractive. (对现在的虚拟)
If only somebody had told me, I would have reminded you. (对过去的虚拟)
If only you could help me next week, I would not be so nervous. (对将来的虚拟)
但更常见的是，if only虚拟条件句单独使用，表示一种假设的祈愿，常译为“要是……就好了。”如：
If only the photos were not lost! (对现在的祈愿)
If only I had seen you three years ago! (对过去的祈愿)
If only I could see him face to face one day! (对将来的祈愿)
三、条件式虚拟语气及其变体在常见考试中的应用
1. 基本形式的应用。基本式主句和从句标志明显，谓语动词形式较固定，因而，难度不大，出现的频率也不高。例如（斜体为正确选项）：
（1）If he_______me tomorrow, I would let him know. (高考模拟试题)
A. should callB. should have calledC. would callD. were calling
（2）If you asked your father you_______permission. (高考模拟试题)
A. may getB. maybe getC. might getD. should have got
（3）The plants would have grown all right if she_______them properly. (CET3-1999/6)
A. had wateredB. wateredC. has wateredD. waters
（4）Jean doesn’t want to work right away because she thinks that if she _______a job she propably wouldn’t be able to see her friends very often. (CET4/6-1996/1)
A. has to getB. were to getC. had gotD. could have got
2. 变体的应用。条件式的各种变体结构多变、形式多样，在各类考试中颇受欢迎。下面是一些代表性的例子（斜体为正确选项）：
（1）_______ today, he would get there by Friday. (高考模拟试题)
A. Would he leaveB. Was he leavingC. Were he goD. If he leaves
（2）_______more careful, his ship would not have sunk. (高考模拟试题)
A. If the captain wereB. Had the captain beenC. Should the captain beD. If the captain would have been
（3）_______ he be interested in that film, he might go to see it with me. (高考模拟试题)
A. ShouldB. WouldC. AreD. Were
(4) Were it not for TV, we _______ the events that are happening in other places.(CET3-1995/6)
A. cannot seeB. could not seeC. cannot have seenD. could not have seen
(5) Should green plants disappear some day,_______ on the earth. (CET3-1996/6)
A. there will hadly be any life B. will there hadly be any lifeC. would there hadly be any life D. there would hadly be any life
(6) Had I been Peter, I_______that way. (CET3-1997/6)
A. won’t talkB. didn’t talkC. wouldn’t have talkedD. wouldn’t talked
(7)_______before we depart the day after tomorrow, we should have a wonderful dinner party. (CET4/6-1997/1)
A. Had they arrivedB. Would they arriveC. Were they arrivingD. Were they to arrive
(8) The millions of calculations involved, had they been done by hand, _______ all practical value by the time they were finished. (CET4/6-2001/6)
A. had lostB. would have lostC. would lostD. should have lost
以上(1)-(8)题为倒装式变体。
(9)_______ the English exam, I would have gone to the concert last Sunday. (高考模拟试题)
A. In spite ofB. But forC. Because ofD. As for
(10) Without the dreams of the youth, this invention might v for a century. (高考模拟试题)
A. have been postponedB. has been postponed C. postponeD. be postponed.
(11) Without your help, we _______ so much in such a short time. (CET3-2001/6)
A. will not achieveB. didn’t achieveC. don’t achieveD. would not have achieved
(12) He was very busy yesterday, otherwise， he _______ to the meeting. (CET3-2004/6)
A. had comeB. cameC. would comeD. would have come
(13) He must have had an accident, or he_______here then. (CET4/6-1990/1)
A. would have been B. had to beC. should beD. would be
(14) We didn’t know his telephone number; otherwise， we _______ him. (CET4/6-1995/6)
A. would have telephoned B. must have telephoned C. would telephone D. had telephoned
以上(9)-(14)题为替代式变体。
(15) Had Paul received six more votes in the last election, he _______ our chairman now. (高考模拟试题)
A. must have beenB. would have beenC. wereD. would be
(16) If you _______ Jerry Brown until recently, you’d think the photo on the right was strange. (高考模拟试题)
A. shouldn’t contactB. didn’t contactC. weren’t to contactD. hadn’t contacted
(17) They would still be missing at sea if a passing ship_______ them. (CET3预测题)
A. did not spotB. had not spot C. was not spottingD. would not spot
(18) If I hadn’t stood under the ladder to catch you when you fell, you_______now. (CET4/6-1999/1)
A. couldn’t have smliedB. wouldn’t be smilingC. didn’t smileD. won’t smile
以上(15)-(18)题为混合式变体。
(19) If only I _______with you last night! (高考模拟试题)
A. wentB. have goneC. could goD. could have gone
(20) If only we_______ a phone! I’m tired of lining up outside the public phone box. (CET3预测题)A. haveB. hadC. will haveD. are to have
(21) Look at the terrible situation I’m in! If only I _______ your advice. (CET4/6-1993/6)
A. followB. had followedC. would followD. have followed
(22) If only the committee v the regulations and put them into effect as soon as possible. (CET4/6-1997/1)
A. approveB. will approveC. can approveD. would approve
以上(16)-(22)题为强化式变体。
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