1、虚拟语气动词的语气表示说话人的态度和看法，可分为陈述语气、祈使语气和虚拟语气。陈述语气用来陈述讲话人认为是事实的事情，有肯定、否定、疑问和感叹等形式。祈使语气用来说明说话人的请求、命令等。虚拟语气表示说话人的愿望、假设或建议，而不表示客观存在的事实。虚拟语气通过谓语动词的特殊形式来表示。1、虚拟语气在条件句中的应用包含条件从句的句子称为条件句。条件句分为两类：一类是真实条件句，一类是虚拟条件句。（1）如果假设的情况很可能发生，就用真实条件句。If he has time, he will come.（2）如果假设的情况发生的可能性不大，则用虚拟条件句虚拟条件句分为三种，见下表：假设情况 条件从
2、句的谓语形式 主句的谓语形式与现在事实相反 过去时（be 的过去时常用were）would/should/might/could+动词原形与将来事实相反 1、过去式2、should+动词原形3、were to+ 动词原形would/should/might/could+动词原形与过去事实相反 过去完成式（had+过去分词） would/should/might/could+have+过去分词If I had lots of money, I would go travelling.If it were to rain tomorrow, the meeting would be put off
3、.If he had received the present, he should have thanked her.2.有关虚拟条件句的几种情况（1）条件从句中的谓语部分有 were, should 和 had 时，if 有时可以省略，这是从句中的主语和谓语要用倒装语序。Were I you, I would go with them.Should I have time, I would call on her.Had it not been for his help, I wouldnt have succeeded.注意 句中的 if it werent for /if it had
4、nt been for 相当于 but for 意为“多亏了 ”， “要不是 ”这两个句型倒装时 not 总是在 it 之后，即 Were it not for /Had it not been for （2）有些条件句中的主句谓语和从句谓语表示的动作在时间上并不一致，这类句子称为错综时间条件句。If youd listened to me, you wouldnt be in such trouble now.If I were you, I wouldnt have missed the movie last night.If they had left home early, they
5、would arrive in half an hour.If Monica should arrive today, she must have started three days ago.（3）有时虚拟语气的条件是通过词或短语表示出来的。There wouldnt be such modern industry without electricity (= if there werent electricity).He is ill. Otherwise (= If he werent ill) he could come.A gentleman (= If he had been a
6、gentleman, he) wouldnt have said so.（4）有些句子随不含条件从句但仍用虚拟语气，这种句子成为含蓄条件句。I would do anything for her.You might have failed.（5）在 if only 引导的句子，but for 引导的短语所在的句子中，常用虚拟语气。if only 要是 就好了；but for 要不是 的话If only I were a flying bird.But for your help, we couldnt have finished the work ahead of time.动词 wish 后
7、的宾语从句见下表：与过去相虚拟 had done与现在相虚拟 did/were与将来相虚拟 would/could/might doI wish I were ten years younger now.I wish I had met him yesterday.I wish I could be a scientist.在表示请求、建议、命令、要求等动词后的宾语从句中，谓语用“should+动词原形” ，should 可省略。常见的这类动词有：suggest，insist ，order，require，advise ，demand，command，ask（要求） ，request，prop
8、ose 等。He suggested that we (should) be there in time.在 would rather 后的宾语从句中，谓语常用过去时来表示现在或将来的情况，用过去完成时表示过去的情况。I would rather you told me the truth.I would rather you had been present.as if/as though 引导的状语从句或表语从句，有时用虚拟语气。从句内容与现在事实相反，谓语动词用一般过去时，be 常用 were；从句内容与过去事实相反，谓语动词用 had+过去分词；表示将来的可能性不大，用 would/m
9、ight/could+动词原形。He looks as if he were a foreigner.He talked as if he had been to many places in the world.It looks as if it might rain.It looks as if our side is going to win.It is (high, about) time 句型中，其后的从句要用虚拟语气，谓语动词常用过去时，也可用 should+动词原形，should 不能省略。It is high time you went there.It is about ti
10、me we should go to bed.It is +形容词/名词+that 句型中，that 从句有时用 should+动词原形，should 可以省略。It is necessary that we be present.Its strange that she should have failed to see her own shortcomings.与表示请求、建议、命令、要求等意义的词相关的主语从句、表语从句和同位语从句中，常用 should+动词原形，其中 should 可省略。It is suggested that he (should) not spend too m
11、uch time watching TV.在 for fear that, in case, lest 引导的，若用虚拟语气时，从句谓语为：should+动词原形，并且 should 不能省略in order that，so that 引导的目的状语从句中，谓语动词一般用can/may/could/might/would/should+动词原形，其中 should 可省略。She walked quietly for fear that she should wake up her roommates.虚拟语气还可用来表示祝愿、诅咒、禁止等。God bless you.May you have a long and happy life.
