新概念英語第二冊(cè)語法精粹：虛擬語氣

虛擬語氣分三種情況來掌握：

1、虛擬條件句。

2、名詞性虛擬語氣。

3、虛擬語氣的其他用語。一、虛擬條件句：條件狀語從句是非真實(shí)情況，在這種情況下要用虛擬語氣。1、條件從句與現(xiàn)在事實(shí)不一致，其句型為：If 主語+過去時(shí)，主語+should(could, would, 或might)+動(dòng)詞原形，如：

If I were you, I would study hard.

If it rained, I would not be here now.2、條件從句與過去事實(shí)不一致，句型為：If 主語+had+過去分詞，主語+should(could, would, 或might)+have+過去分詞，如：

If the doctor had come last night, the boy would have saved.

If I had not studied hard, I would have failed in the exam last term.3、條件從句與將來事實(shí)不一致，句型為：If 主語+should(were to, 過去時(shí))+do，主語+should(could...)+原形do，如：

If it should rain tomorrow, we would stay at home.

If I were to go to the moon one day, I could see it with my own eyes.

If you missed the film to night, you would feel sorry.注意問題：1、If條件句中絕對(duì)不可出現(xiàn)"would"。2、根據(jù)句中的時(shí)間狀語，有時(shí)可能出現(xiàn)“混合虛擬”的情況，即主句可能是現(xiàn)在的情況，條件句也許是發(fā)生在過去的情況，但都是遵守上述句型。3、在條件句中如果出現(xiàn)were, had, should可省去if，將主語與這些詞倒裝，例如：

Had the doctor come last night, the boy would have saved.

Were I to go to the moon one day, I would see it with my own eyes.

Should it rain tomorrow, we would stay at home.二、名詞性虛擬語氣：在表示命令、建議要求、驚嘆時(shí)的名詞性從句中需用虛擬語氣，基本句型：主語+(should)+動(dòng)詞原形，如：Mother insisted that John go to bed at 9 o'clock.(賓語從句)

We suggested that the meeting should not be held.

It was required that the crops should be harvested at once.(主語從句)

The suggestion that he be invited was rejected.(同位語從句)

That is their demand that their wages be increased.(表語從句)注意：在這種句子中絕不出現(xiàn)"would""must""could"等。三、虛擬語氣在一些特殊詞中的使用或含蓄條件句：1、wish后的賓語從句：

與現(xiàn)在愿望不一致——主語+過去時(shí)：I wish I were you.

與過去愿望不一致——主語+had+過去分詞：I wish I had visited the white House when I was in the states.

與未來愿望不一致——主語+would(could)+原形：I wish I could meet you tomorrow at the party.2、It's time句型：

當(dāng)It's time后用that從句時(shí)應(yīng)該為“主語+should+原形”或“主語+過去時(shí)”，例如：

It's time that you went to school. 或It's time that you should go to school.3、If only引起的感嘆句相當(dāng)于“How I wish+賓語從句”：

If only he could come! 他要能來就好了。

If only I had known the answer! 我要早知答案就好了。4、would rather, as if(though)引導(dǎo)的句子也需使用虛擬，表示過去的情況用過去完成時(shí)，表示現(xiàn)在與將來的情況用過去時(shí)，如：

I'd rather you posted the letter right away.

I'd rather you had returned the book yesterday.

She loves the children as if they were hers.

Alan talked about Rome as if he had been there.5、without, but, but for, otherwise引起的短語或句子常暗含著含蓄條件：

Without you, I would never know him.

But for your cooperation, we wouldn't have done the work so well. = If it were not for your cooperation, we wouldn't have done the work so well.

(注：without / but for... = If it was not for.../ If it hadn't been for...)

But that she was afraid, she would have said no.

I would be most glad to help you, but I' am busy now.

I am busy now; otherwise I would do you the favor!專項(xiàng)訓(xùn)練1、It is important that a college student ______ a foreign language.

A.will master B.master C.masters D.would master2、It is strange that she ______ without saying a word.

A.should have gone out B.went C.should go out D.goes out3、If my lawyer ______ here last Saturday, he ______ me from going.

A.had been, would have prevented B.had been, would prevent C.were, would prevent D.were, would have prevent4、 ——“He is a brave man.”

——“Yes, I wish I ______ his courage.”

A.have B.had C.will have D.may have5、If it ______ rain, the crops would be saved.

A.should B.will C.is going to D.was to6、He ordered that the medicine ______ by a special plane.

A.was sent B.would be sent C.should send D.be sent7、If you ______ the medicine, you ______ better now.

A.took, would feel B.had taken, felt C.had taken, would feel D.took, would have felt8、She is my sister, but she often acts as if ______ my mother.

A.is B.was C.were D.had been9、I went to bed early last night, but I wish I ______ so.

A.didn’t do B.hadn’t done C.haven’t done D.couldn’t do10、I’d rather he ______ tomorrow afternoon.

A.will come B.comes C.coming D.came(后設(shè)答案，大家不要偷看哦~(*^__^*) 嘻嘻……)KEYS

1、B 2、A 3、A 4、B 5、A 6、D 7、C 8、C 9、B 10、D