虚拟语气基础知识梳理

王新民

虚拟语气是高中英语语法的难点之一。在近年来的高考试题中，虚拟语气不断出现。因此，掌握好虚拟语气，对于我们正确地理解英语会有很大的帮助，从而直接或间接地提高我们的高考分数。

一、虚拟语气在含有非真实条件状语从句的主从复合句中的应用

如果条件状语从句叙述的情况与已经发生情况相反，或者在未来发生的可能性极小，甚至根本不可能发生，这种条件状语从句称为非真实条件句。虚拟语气在含有非真实条件状语从句的主从复合句中的应用有以下几种情况：

（一）与过去事实相反的假设

其基本句型是：

“If+主语+had done， 主语+should/would/could/might have done”。如：

If I had taken the teacher's advice，I would have gone to college.

（二）与目前事实相反的假设

其基本句型是：

“If+主语+did（be动词常用were），主语+should/could/would/might do”.如：

If I were you，I would follow the teacher's advice.

（三）对未来几乎不可能发生的情况的假设

对于未来的情况，如果发生和不发生的可能性同时存在，我们还是要用真实条件句。只有当发生的可能性极小或者根本不可能发生的时候才用非真实条件句。其基本句型是：

“If+主语+should do/were to do//did，主语+should/could/would//might do”.如：

If it were to rain tomorrow，I would give you 100，000，000 US dollars.

[注意]

（一）有时，某些介词短语、副词或连词的作用相当于非真实条件句。如：

Without his help，I couldn't have finished this task in such a short time.

He phoned to inform me of your birthday，oy I would have forgotten it.

（二）若从句的谓语中有助动词had， should 或were，可把这些词提到句首，而省略掉If。如：

Had I had enough money，I would have bought the house.

Should he come，tell him to ring me up.

Were I you，I would go with him.

（三）若条件句和主句的时间不一致，则要根据各自的时间使用相应的虚拟语气的谓语动词形式。如：

If I were you，I would have chosen the English department at that time.

If you had taken my advice just now，you would be better now.

二、虚拟语气在其他状语从句中的应用

（一）在so that或in order that引导的目的状语从句中，常常使用虚拟语气，其结构如下：

①当主句的谓语动词是现在时或将来时时，从句的谓语动词前要加may，can或will。如：

Please give me a little more time so that I can perfect it.

②当主语的谓语动词是过去时时，从句的谓语动词前要加could，should，might或would。如：

Our teacher spoke slowly so that we could hear clearly.

（二）当as if或as though引导的方式状语从句所表达的内容与实际情况相反或者纯粹是一种假设时，句子中通常使用虚拟语气，其结构如下：

①从句用动词的过去式表示从句的动作和主句的动作同时发生。如：

He speaks as if he were an Englishman.

②从句用“had+过去分词”表示从句的动作发生在主句动作之前。如：

She was very heppy as if she had won the contest.

三、虚拟语气在宾语从句中的应用

（一）wish后的宾语从句必须用虚拟语气。其结构和as if或as though引导的方式状语从句里的虚拟语气相同。如：

I wish I were a bird and could fly freely in the sky.

I wish I had seen the film last night.

（二）suggest，order，demand，insist等动词之后的宾语从句也常常使用虚拟语气，其构成是“should+动词原形”，其中的should可以省略。如：

Our teacher suggested that we read more books in our spare time.

[注意]

（一）susgest在表示“建议”时，其后的宾语从句可以用虚拟语气；在表示“暗示；表明”时，要用陈述语气。如：

The smile on his face suggested that he was satisfied with our work.

（二）insist在表示“坚持要”时，其后的宾语从句要用虚拟语气；在表示“坚持说”时，要用陈述语气。如：

The little boy insisted that he had never stolen the money.