虚拟语气中的could/should/might/would的用法

（一） 非真实条件句中的虚拟语气
1 与现在事实相反
If + S. + were / V-ed … ， S. +should / would / could / might + V 原 … . （diyi人称可以用should，所有人称都可以用would）
l If I were you ， I should go there with him . 如果我是你，就和他一起去那里。
l If I knew his address ， I might go to visit him . 如果我知道他的地址，也许我会去看他。
l Tom would be mad if he were here . 汤姆如果在这儿会发疯的。
l If there were no water ， there would be no life on the earth . 如果没有水，地球上就没有生命。
2 与过去事实相反
① If + S. + had + P.P. + …， S. + should / would / could / might + have + P.P. … . （主句表示过去）
②If + S. + had + P.P. + …， S. + should / would / could / might + V 原 …. （主句表示现在）
l If he had been there last night ， he would have known what had happened . 如果他昨晚在那里，他就会知道发生了什么事。
l If you had left earlier ， you wouldn’t have missed the plane. 如果你早一点动身，你就不会错过飞机了。
l If I had gone to the party last night ， I would have seen Tom . 如果我昨晚去了那个聚会，我就会看见汤姆了。
l If I had gone to the zoo yesterday ， I would be very tired now . 如果我昨天去了动物园，我现在就会很累。
l If he had finished his homework yesterday ， he could play soccer with his friends now . 如果他昨天写完作业，现在就可以和朋友们踢足球了。
3 与将来事实相反
① If + S. + were / V-ed … ， S. +should / would / could / might + V 原 … . （表示虚拟）
②If + S. +should / would / could / might + V 原 …， S. +should / would / could / might + V 原 … .（不表示虚拟，表示客气）
l If we went to help him tomorrow ， he would be very happy . 如果明天我们去帮助他，他会很开心的。
l If it were Sunday tomorrow ， I would take you to the park .
l If we didn’t go to see him next week ， he would be very angry .
l If you could send me your price list at once ， I would be very grateful .
l If you could help me with my English ， I would be very happy .

* 1 如果条件句中省略if ，句子要倒装。
l Were I you ， I wouldn’t smoke . = If I were you ， I wouldn’t smoke . 如果我是你的话，我就不抽烟。
l Had he read the material ， he would have been able to answer the question . 如果他读了资料，他就能回答这个问题。
= I he had read the material ， he would have been able to answer the question .
l Would he come here tomorrow ， I would tell him about it . 如果明天他来这里，我会告诉他这件事。
= If he would come here tomorrow ， I would tell him about it .
l Could the blind see ， they would value their sight more than we do . 如果盲人能看见东西的话，他们会比我们更珍惜光明。
= If the blind could see ， they would value their sight more than we do .

2 有时条件状语从句和主句动作发生的时间不一致，这时，动词的形式要根据具体意义来决定，这种句子被称为错综时间的虚拟条件句。
l If he were a doctor ， his neior would have been saved last night . 如果他是一个医生，他的邻居昨晚就会得救了。
l If you had gone through a lot of hardship ， you would know what a happy life you are living . 如果你经历过很多艰辛，你就会知道现在的生活是多么幸福。
l If you had studied hard at school ， you would have a good job now . 如果你当初在学校努力学习，现在就会有一份好工作了。
l If they hadn’t lent us the money ， we would still be living a poor life now . 如果他们当初没借给我们钱，我们现在仍然过着贫苦的生活。

3 有时非真实的条件状语从句并没有出现，这种假设的条件是通过某些短语或上下文含蓄地表达的，这种句子叫做含蓄条件句。常见的词或短语有：but for (要不是) ，
but that (要不是) ， without (没有) ， otherwise (否则) ， or (否则) ， but ……
l But for the rain ， we should have a pleasant journey . （表现在）
l But for his poverty ， he would have gone abroad . （表过去）
l Without your help ， I wouldn’t have succeeded . （表过去）
l He wasn’t careful enough ， the accident could have been avoided . （表过去）他不够细心，否则的话事故是能够避免的。
= If he had been careful enough ， the accident could have been avoided .

（二） 其他情况下的虚拟语气
1 某些表示建议、命令、主张、要求的动词后宾语从句中要用虚拟语气，其谓语形式为“should + V 原”，should 可以省略。这类动词有：
① 表建议：suggest（建议） propose （建议） recommend（建议） advise （建议） move（建议，鼓动）
② 表主张：insist（坚持） maintain（主张） hold（主张） urge （呼吁，力劝）
③ 表要求：ask （要求） request（要求） require（要求） demand（要求） desire（要求，希求） prefer（宁愿） arrange（安排）
④ 表命令：order（命令） command（命令）
*suggest: 表示“建议”时，宾语从句用虚拟语气；但是表示“暗示，使人想到”时，宾语从句不用虚拟语气。
Insist: 表示“坚持（应该）”时，宾语从句用虚拟语气；但是表示“力言，坚持（认为），坚持（说）”时，宾语从句不用虚拟语气。
l He suggests that we ( should ) have a meeting . 他建议我们开个会。
l His attitude suggests that he isn’t interested in it . 他的态度暗示他对此不感兴趣。
l He insisted that he hadn’t taken the money . 他坚持说他没拿那些钱。
l I advised that he ( should ) go on a diet . 我建议他节食。
l They demanded that their working conditions ( should ) be bettered . 他们要求改善工作条件。

2 wish（希望）， would rather（宁愿）， would sooner（宁愿）， had rather（宁愿），would just as soon（宁愿）等表示愿望的动词后宾语从句中要用虚拟语气。
l I wish that I were thinner . 要是我再瘦点就好了。（表现在）
l I wish that I hadn’t eaten too much . 要是我没吃那么多就好了。（表过去）
l I wish that I would visit the moon some day . 我希望有一天去参观月球。（表将来）
(wish + 宾语从句→表示不能实现或者难以实现的愿望，汉语常译为“可惜……，……就好了，悔不该……，但愿……” )
l I’d rather that you didn’t open the door . 但愿你别开门。
l I’d just rather you stayed at home today . 但愿你今天呆在家里。
l I’d just as soon that I hadn’t told her this yesterday . 真希望昨天没有把这些告诉她。

3 在主语从句中，谓语动词的虚拟语气结构要用“should + V 原”，should 可以省略。这种结构用来表示惊奇，不相信，惋惜，理应如此等意义。但如果不表示惊奇，主语从句也可以用陈述语气。
① It’s + 过去分词 （suggested ， ordered ， commanded ， advised ， required ， requested ， urged， asked ， decided ， desired ……）that …
② It’s + 形容词（necessary ， important ， better ， strange ， vital生死攸关的， 重大的， urgent ， essential本质的，精华的， appropriate适当的， advisable可取的， 明智的， imperative .命令的， 强制的， 紧急的， 必要的， desirable ， natural ……）that …
③ It’s + 名词（a pity ， a shame ， no wonder ……）that …
l It’s suggested that the store ( should ) be closed at eight p.m. . 有人建议商店八点关门。
l It’s important that you ( should ) book the ticket in advance . 你一定要提前订票。
l It’s necessary that young and old people ( should ) communicate more with each other . 老人和年轻人之间必须要有更多的交流。
l It’s a pity that she ( should ) be so careless . 她竟然如此马虎，太让人遗憾了。
l It’s strange that he ( should ) be absent today . 他今天竟然缺席，这太奇怪了。
l It’s a pity that you can’t swim . 真遗憾，你不会游泳。（不表示惊奇）
l It’s strange that he didn’t come yesterday . 真奇怪，他昨天没来。（不表示惊奇）

4 某些表示建议，命令，要求等名词后面的表语从句或同位语从句中要用虚拟语气，其谓语形式为“should + V 原”，should 可以省略。这类词有：suggestion ， proposal提议；建议， advice ， request ， requirement ， desire ， demand ， idea ， plan ， motion动机，意向；请求 ， order ， recommendation ……
l My suggestion is that we ( should ) help her . 我的建议是我们帮她。 （表语从句）
l The order were that we ( should ) stay where we were . 命令是我们仍留在原处。（表语从句）
l His requirement is that every student ( should ) write two papers . 他的要求是每个学生都要写两篇论文。（表语从句）
l At the meeting he put forward the suggestion that we ( should ) go there on the weekend . 在会上，他提出我们周末去那里。 （同位语从句）
l We all agreed to his idea that we ( should ) go swimming on Sunday . 我们都同意他的主意：星期天去游泳。（同位语从句）

5 as if ， as though 引导的表语从句或方式状语从句中，要用虚拟语气。但是如果从句中“好像，似乎”的东西与事实相近时，则要用陈述语气。
l She loves the child as if he were her own . 她爱那个孩子，好像他是她亲生的。
l He stands there as if he were frozen . 他站在那儿一动不动，好像冻僵了一样。
l He looked as if he had never seen the sea . 他看上去好像从没见过大海似的。
l He talked about Shanghaias if / as though he had been there before . 他谈论着上海，好像他以前去过似的。
l It looks as if it is going to rain . 看上去天要下雨了。（陈述语气）
l The milk smells as if it is fresh . 牛奶闻上去是鲜的。（陈述语气）
l It looks as if they have known each other for years . 他们看上去好像已经认识多年了。（陈述语气）
l Tom looks as if he is putting on weight . 汤姆看上去正在发胖。（陈述语气）
l The dress feels as if it is made of cotton . 衣服摸上去好像是棉的。（陈述语气）

6 even if ， even though 引导的让步状语从句中，用虚拟语气，但如果叙述的是事实，则要用陈述语气。
l Even if he were wrong ， you shouldn’t treat him like that . 即使他错了，你也不该那样对待他。
l Even though I were as rich as you ， I wouldn’t buy that big house . 即使我像你一样富有，我也不会买那个大房子。
l I like him even if he isn’t rich . 即使他不富有，我也喜欢他。（陈述语气）
l His grades were always excellent ， even if / even though he was often absent . 即使他经常缺席，他的成绩也一直很优异。（陈述语气）

7 in case (以免) ，lest (以免)， for fear that (以免) 引导的目的状语从句中，常用“should + V 原”表示虚拟，should 可以省略。但是，so that (为了)，in order that (为了) 引导的目的状语从句中，常用may / might / can / could + V 原 这一结构。
l I’ll ring you up lest you ( should ) forget to come . 我会给你打电话，以免你忘了来。
l I wrote down the name for fear that I ( should ) forget it . 我把名字写下来省得忘了。
l He doesn’t dare to leave the house in case he ( should ) be recognized . 他不敢离开那个房子，以防被认出来。
l Better chain up the dog in case he bites . Z好把狗拴好，以免它咬人。（陈述语气）
l Take your coat in case the weather is cold . 带上你的外衣，以防天气变冷。（陈述语气）
l I study hard so that I can pass the exam . 我努力学习为了通过考试。
l He gets up early in order that he can catch the first bus . 他早起为了赶上头班车。
l They elected the best grapes so that they could make the best wine . 他们为了酿Z美的酒挑选了Z好的葡萄。

8 在 It’s time … / It’s high time … / It’s about time … 后面的定于从句中常用虚拟语气，谓语动词多数使用“过去式”，也可以用“should + V 原”，但是should 不可以省略。
l It’s time that you went to bed . 你该上床睡觉了。
l It’s about time that you went to school . 你该上学了。
l Its’ high time that we started to work . 我们该开始工作了。
l It’s time that we should leave . 我们现在该走了。
l It’s high time that you got the computer repaired . 你该找人修修电脑了。

9 在if only 引导的感叹句中多用虚拟语气。
l If only I were a bird ! 如果我是一只鸟就好了。
l If only I had taken his advice ! 我要是听他的话就好了。
l If only I could take back those words ! 要是我能收回那些话该多好啊！
l If only he hadn’t taken me to the supermarket ， I wouldn’t have got lost . 要是他没把我带到超市去，我就不会丢了。

10 在expect ， believe ， think ，suppose等动词否定式或疑问式后面的宾语从句中，及在It’s a pity ( shame )， It’s surprising ( strange ， amazing ， unthinkable ， incredible …)that… 后面的主语从句中，常用“should + V 原”，表示吃惊，怀疑，不满等语气。另外，在be sorry ， be surprised ， be disappointed that …后面的原因状语从句中，常用“should + V 原”，表示吃惊，怀疑，不满，遗憾等语气。
l We never expected that they should have lost the game . 我们没预料到他们这次比赛会输。
l I couldn’t believe that he should steal my car . 我简直不相信他竟然偷我的车。
l It’s incredible that he should have cheated at cards . 他打牌作弊，这太不可思议了。
l I’m sorry that he should be late again . 他又迟到了，真让我感到遗憾。
l We are surprised that he should be mayor . 我们感到非常吃惊，他竟然是市长。

11 虚拟语气用在If it were not for … “如果没有……”（与现在事实相反），If it had not been for … “如果当时没有……”（与过去事实相反）中。
l If it were not for the rain ，the crops should / would die . 如果没有雨水的话，庄稼现在就死了。
l If it had not been for your timely help ， I would have failed . 如果没有你及时的帮忙，我就失败了。

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