1、虚拟语气详解虚拟语气表示说话人的主观愿望（往往与客观事实相反） ，或是表示假象和猜测。虚拟语气无论从形式上还是时态上都比较复杂，需要归类记忆。虚拟语气大体分为三类：(1) be 型虚拟 (2) were 型虚拟 (3) if 条件句及主句虚拟下面会详细说每种虚拟形式的特征和规律，考试时先判断属于哪种虚拟类型，剩下的皆是套路（1）be 型虚拟（基本是套路）形式：should + 动词原形，should 可以省略用法：1） 表示“ 命令、建议、要求 ”等意义词语之后的宾语从句用 be 型虚拟，常见的词如下: demand, desire, insist, order, ask, command,
2、propose, recommend, suggest, prefer, require, request 等最常见的形式是这类动词后面接着一个宾语从句，则宾语从句的谓语部分要用（should）+ 动词原形来虚拟例: We demand that the meeting（should）be postponed.The manager suggested that we (should) work together.注意：有时候你所见到不一定是上述动词引导的宾语从句，而是由上述词变体后所引导主语从句(it 做形式主语，如：it is advised/ suggested/ requested/
3、ordered/ proposed that)、表语从句或同位语从句例如：It is required that the students (should) learn a foreign language. (主语从句)The requirement is that all the equipment in the meeting room (should) be checked twice before. (表语从句 )We didnt stand for his proposal that the meeting (should)be postponed. (同位语从句)只要看到句中有上
4、述动词或其变体，不管词性怎么变、句型怎么变，都用 be 型虚拟！特例：suggest 和 insist 这两个比较特殊， 当 suggest 作“暗示、表明、说明”讲，insist 作“坚持说”讲，后面一般跟的是客观事实，不需要虚拟 这是一个比较重要的考点，体会下面两组句子：We all suggest that a lab (should) be built. 我们都建议建一个实验室。Her expression suggests that she is angry. 她的表情说明她生气了。She insisted that we should find the source of the
5、river. 她坚持主张我们应该找到河的源头。She insisted that she had done nothing wrong. 她坚持说自己没做错事。suggest 的区别很明显，但 insist 有点难辨别，一般来说如果 insist 后面跟的是某种主张，或是坚持要做一件事，那么用虚拟。2）表示主观看法，常表示“某事是必要的、重要的。 。 。怎么怎么样的” ，尤其是在“ it is +名词/形容词+ that 从句”结构中，常见的形容词包括： advisable, desirable, essential, imperative, important, necessary, obl
6、igatory, proper, dispensable, impossible, natural, surprising 等例如：It is advisable that you (should) leave now. It is necessary that teenagers (should) take part in outside activities.It is of great importance that smoking (should) be banned in public area.依旧是套路，熟悉这些关键提示词即可3）表示“恐怕，担心，以免，万一” 等，例如：if,
7、lest, in case, for fear that 等，后面的从句用（should）+ 动词原形来虚拟注意：这里的 if 不是引导条件句，而是表示“以防”、 “万一”例：He took his raincoat with him in case it (should) rain.He took his raincoat with him for fear that he (should) be caught in the rain.4）be 型虚拟还用于表示“ 祝愿”的特殊结构，通常是 May + 主语 + 动词原形例：May you be happy.几乎不考，了解即可（2）were
8、型虚拟（要推时态）表达与事实情况相反、未曾实现的主观愿望，形式如下：主观表达的愿望 从句谓语的形式与现在事实相反的愿望 过去式（ be 动词一律用 were）与过去事实相反的愿望 过去完成式 had +过去分词与将来事实相反的愿望 过去将来式 would/ could +动词原形用法：1）wish 引导的宾语从句，表示“希望”例：I wish I were a bird. ( 对现在情况的虚拟 )I wish you came here now. (我希望你现在就来)I wish that I had passed the final exam. (对过去情况虚拟，实际上未通过考试 )I wi
9、sh he would/ could come to help me with my paper, but he will go on business next week. (对将来情况虚拟，实际上下周来不了) 注意句子里的时间标志，有时没有时间标志，就需要自行体会2）if only 引导的感叹句，表示“要是就好了”例：If only she were here at this moment. 要是她此刻在这儿就好了。If only I hadnt made this mistake. 要是我没犯这个错误就好了。If only you would / could attend my wedd
10、ing. 要是你能来参加我的婚礼就好了。 （现在也会用过去式表示将来，但是表示将来的不怎么会考，所以无需纠结）3）would rather, would sooner, would prefer, had rather 等引导的宾语从句，表示“宁愿，但愿 ”例：I would rather you came here now.l would rather he hadnt told me the truth.Id rather you went tomorrow. (同样也会用过去式表示将来 )4）as if / as though 引导的状语从句，表示“似乎 ，好像.” ，与事实情况相反或几
11、乎不大可能会发生例：She speaks as though she were sick.He talked about the film as if he had seen it before. It seems as if the meeting would never end.注意：如果 as if / as though 后面跟的是事实或者近乎事实，则不需要虚拟，只能意会不能言传，对比一下下面两句话就知道了，但这并不是高频考点It seems as if he has no worries. 看起来他似乎没有烦恼，是真的没有烦恼。It seems as if he had no wor
12、ries. 他只是看起来没烦恼，其实内心世界很纠结。（3）if 条件句及主句虚拟if 引导的条件句分为真实条件句和非真实条件句，非真实条件句的主句和从句都要用虚拟语气,表示根本不存在的情况或可能性很小的假设。主句和从句都有一定套路，而且要根据时态搭配使用，具体见下表：从句（if） 主句与现在事实相反 过去式（be 动词都用 were） would/ could/ might/ should +动词原形与过去事实相反 过去完成式 would/ could/ might/ should +现在完成时与将来事实相反 过去式/ should+ 动词原形/ were to do would/ could
13、/ might/ should +动词原形例：If I had enough money, I would buy myself a computer.If we had had enough rain last year, we could have gained a good harvest.If I should see/ were to see/ saw him tomorrow, I would invite him home.would, could, might, should 在意思上稍有区别，would 语气肯定，表示十有八九会出现的结果；could 表示能够；might 表
14、示或许；should 表示应该，但这个区别真的不重要考试也不会在这个上面做文章，自己稍稍理解体会，留个印象就行。注意 1：表格中的是最基本的规则，主句和从句发生在同一个时空（假如我当初怎样，那么我当时就会怎样，都是发生在过去时间；假如我现在怎样，我现在就会怎么怎么，都是发生在当下） 。但也会有些情况，主从句动作发生的时间不一致（假如我以前怎么样，我现在就会怎样；假如我现在怎样， 我将来就会怎样。 ）我们把这种类型的句子称作“错综时间” 虚拟条件句 ，看上去很厉害的样子，其实只需要把主从句分开独立分析，看主、从句分别是对什么时间的虚拟，各自对应表格就行。关键是先判断主、从句发生时间是否一致，考试
15、很喜欢考例：If you had worked hard, you would be very tired. 如果你刚才认真工作了，你现在就会很累。主句对现在虚拟，从句对过去虚拟。If you followed my advice now, you would succeed in the final exam next month.要是你现在听我的话，下个月的期末考肯定没问题。主句对将来虚拟，从句对现在虚拟。注意 2：虚实混用，有的部分是真实的，有的部分是虚拟的，非真实的部分才虚拟，真实的部分用正常语法形式例：If I had been at the concert yesterday ev
16、ening, I should have met the famous singer. But I failed to get a ticket. 前面是对过去的虚拟，是没发生的，但是没买到是真实发生的，所以正常用过去式即可。注意 3：倒装结构：if 从句中如果含有 were，should，had 时可以省略 if，将were，should，had 倒装至主语之前。例：If I were you, I would apply for the job. Were I you, I would apply for the job.If you had taken my advice, you wo
17、uldnt have failed in the examination. Had you taken my advice, you wouldnt have failed in the examination.If he should arrive there in advance, I would show him around London. Should he arrive there in advance, I would show him around London.注意 4：有时假设的情况并不用 if 从句表示出来，而是通过一个介词 /介词短语（without, but for
18、等） 、副词（otherwise） 、连词（or, but, but that 等） 、were it not for、had it not been for, 这属于含蓄的虚拟语气。虽然没出现 if，还是按照前面说的套路来例：Without air, there wouldnt be living things in the world.But for your advice, I would have failed.He came to town yesterday, otherwise/ or I would not have met him.She would have come to
19、 see you, but she was so busy that day.注意：were it not for +名词/名词短语、had it not been for +名词/名词短语，这两个结构也是倒装后的形式，意思是“要不是” 还原成 if 虚拟条件句如下：If it were not for peace，we could not live a happy life.= Were it not for peace，we could not live a happy life.If it had not been for your help, I would have gone ban
20、krupt.= Had it not been for your help, I would have gone bankrupt.特殊虚拟结构(1) It is (high/ about) time 句型中，从句谓语动词用过去式或者用 should(不可省) + 动词原形，意思是该做某事的时候到了例：It is high time we went to bed. = It is high time we should go to bed.(2) 动词 intend, mean, plan, want, expect, hope 使用虚拟语气，用过去完成式 + 动词不定式表示“ 过去想做却没做的事 ”例：I had intended to attend the meeting, but I was ill. 我本想参会的，但我生病了。
