王新民

虛擬語氣是高中英語語法的難點(diǎn)之一。在近年來的高考試題中，虛擬語氣不斷出現(xiàn)。因此，掌握好虛擬語氣，對于我們正確地理解英語會有很大的幫助，從而直接或間接地提高我們的高考分?jǐn)?shù)。

一、虛擬語氣在含有非真實(shí)條件狀語從句的主從復(fù)合句中的應(yīng)用

如果條件狀語從句敘述的情況與已經(jīng)發(fā)生情況相反，或者在未來發(fā)生的可能性極小，甚至根本不可能發(fā)生，這種條件狀語從句稱為非真實(shí)條件句。虛擬語氣在含有非真實(shí)條件狀語從句的主從復(fù)合句中的應(yīng)用有以下幾種情況：

（一）與過去事實(shí)相反的假設(shè)

其基本句型是：

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

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

（二）與目前事實(shí)相反的假設(shè)

其基本句型是：

“If+主語+did（be動詞常用were），主語+should/could/would/might do”.如：

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

（三）對未來幾乎不可能發(fā)生的情況的假設(shè)

對于未來的情況，如果發(fā)生和不發(fā)生的可能性同時存在，我們還是要用真實(shí)條件句。只有當(dāng)發(fā)生的可能性極小或者根本不可能發(fā)生的時候才用非真實(shí)條件句。其基本句型是：

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

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

[注意]

（一）有時，某些介詞短語、副詞或連詞的作用相當(dāng)于非真實(shí)條件句。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）若從句的謂語中有助動詞had， should 或were，可把這些詞提到句首，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）若條件句和主句的時間不一致，則要根據(jù)各自的時間使用相應(yīng)的虛擬語氣的謂語動詞形式。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、虛擬語氣在其他狀語從句中的應(yīng)用

（一）在so that或in order that引導(dǎo)的目的狀語從句中，常常使用虛擬語氣，其結(jié)構(gòu)如下：

①當(dāng)主句的謂語動詞是現(xiàn)在時或?qū)頃r時，從句的謂語動詞前要加may，can或will。如：

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

②當(dāng)主語的謂語動詞是過去時時，從句的謂語動詞前要加could，should，might或would。如：

Our teacher spoke slowly so that we could hear clearly.

（二）當(dāng)as if或as though引導(dǎo)的方式狀語從句所表達(dá)的內(nèi)容與實(shí)際情況相反或者純粹是一種假設(shè)時，句子中通常使用虛擬語氣，其結(jié)構(gòu)如下：

①從句用動詞的過去式表示從句的動作和主句的動作同時發(fā)生。如：

He speaks as if he were an Englishman.

②從句用“had+過去分詞”表示從句的動作發(fā)生在主句動作之前。如：

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

三、虛擬語氣在賓語從句中的應(yīng)用

（一）wish后的賓語從句必須用虛擬語氣。其結(jié)構(gòu)和as if或as though引導(dǎo)的方式狀語從句里的虛擬語氣相同。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等動詞之后的賓語從句也常常使用虛擬語氣，其構(gòu)成是“should+動詞原形”，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“建議”時，其后的賓語從句可以用虛擬語氣；在表示“暗示；表明”時，要用陳述語氣。如：

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

（二）insist在表示“堅(jiān)持要”時，其后的賓語從句要用虛擬語氣；在表示“堅(jiān)持說”時，要用陳述語氣。如：

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