初中虛擬語氣知識點歸納

　　虛擬語氣用來表示說話人的主觀愿望或假想，所說的是一個條件，不一定是事實，或與事實相反。在條件句中的應用條件句可分為兩類，一類為真實條件句，一類為非真實條件句。非真實條件句表示的是假設的或?qū)嶋H可能性不大的情況，故采用虛擬語氣。

　　一、真實條件句：

　　真實條件句真實條件句用于陳述語氣，假設的情況可能發(fā)生，其中if是如果的意思。

　　時態(tài)關系句型：

　　條件從句：一般現(xiàn)在時;

　　主句：shall/will+動詞原形

　　如：If he comes, he will bring his violin.

　　注意：

　　1)在真實條件句中，主句不能用be going to表示將來，該用shall, will。

　　如： (錯) If you leave now, you are never going to regret it.

　　(對) If you leave now, you will never regret it.

　　2)表示真理時，主句謂語動詞便不用shall(will)+動詞原形，而直接用一般現(xiàn)在時的動詞形式。

　　二、非真實條件句：

　　非真實條件句表示的是假設的或?qū)嶋H可能性不大的情況，故采用虛擬語氣。

　　1)時態(tài)：可以表示過去，現(xiàn)在和將來的情況。它的基本特點是時態(tài)退后。

　　a. 同現(xiàn)在事實相反的假設。

　　句型：從句：一般過去時;主句：should(would)+動詞原形

　　如：If they were here, they would help you.

　　b.表示于過去事實相反的假設。

　　句型：條件從句：過去完成時;主句：should(would)have+過去分詞

　　如：If she had worked harder, she would have succeeded.

　　The rice would not have been burnt if you had been more careful.

　　If my lawyer had been here last Saturday, he would have prevented me from going.

　　c.表示對將來的假想句型：

　　條件從句：一般過去時;主句：should+動詞原形

　　從句： were+不定式;主句：would+動詞原形 should+動詞原形

　　如：If you succeeded, everything would be all right.

　　If you should succeed, everything would be all right.

　　If you were to succeed, everything would be all right.

　　三、混合條件句：

　　主句與從句的動作發(fā)生在不同的時間，這時主，從句謂語動詞的虛擬語氣形式因時間不同而不同，這叫做混合條件句。

　　如：

　　If you had asked him yesterday, you would know what to do now. (從句與過去事實相反，主句與現(xiàn)在事實相反。)

　　If it had rained last night (過去), it would be very cold today (現(xiàn)在).

　　比較if only與only if：

　　only if表示“只有”;if only則表示“如果……就好了”。If only也可用于陳述語氣。

　　如：I wake up only if the alarm clock rings. 只有鬧鐘響了，我才會醒。

　　If only the alarm clock had rung. 當時鬧鐘響了，就好了。

　　If only he comes early. 但愿他早點回來。

　　It is(high) time that It is(high) time that 后面的從句謂語動詞要用過去式或用should加動詞原形，但should不可省略。

　　如：It is time that the children went to bed.

　　It is high time that the children should go to bed.

　　need“不必做”和“本不該做"”

　　didn't need to do表示：過去不必做某事，事實上也沒做。

　　needn'thavedone表示：過去不必做某事，但事實上做了。

　　如：John went to the station with the car to meet Mary, so she didn't need to walk back home. 約翰開車去車站接瑪麗，所以她不必步行回家了。

　　John went to the station with the car to meet Mary, so she needn't have walked back home. 約翰開車去車站接瑪麗，所以她本不必步行回家了。(Mary步行回家，沒有遇上John的車。)

　　特殊的虛擬語氣詞should 的用法：

　　1)It is demanded/necessary/a pity+that…結構中的主語從句的謂語動詞要用should加動詞原形，should可省略。

　　句型：

　　如：It is suggested that we(should) hold a meeting next week.

　　It is necessary that he(should) come to our meeting tomorrow.

　　2)在賓語從句中的應用在表示命令、建議、要求等一類動詞后面的從句中。order, suggest, propose, require, demand, request, insist, command, insist+(should)do

　　如：I suggest that we(should) hold a meeting next week.

　　He insisted that he(should) be sent there.

　　注意：如suggest, insist不表示“建議”或“堅持要某人做某事時”，即它們用于其本意“暗示、表明”、“堅持認為”時，賓語從句用陳述語氣。

　　如：The guard at gate insisted that everybody obey the rules.

　　判斷改錯：(錯)You pale face suggests that you(should) be ill.

　　(對)Your pale face suggests that you are ill.

　　(錯)I insisted that you(should) be wrong.

　　(對)I insisted that you were wrong.

　　3)在表語從句，同位語從句中的應用在suggestion, proposal, idea, plan, order, advice等名詞后面的表語從句、同位語從句中要用虛擬語氣，即(should)+動詞原形。

　　如：My idea is that we(should) get more people to attend the conference.

　　I make a proposal that we(should) hold a meeting next week.

　　虛擬語氣知識體系：

　　條件從句中的謂語動詞形式主句中的謂語動詞形式

　　與過去事實相反had+過去分詞should/would+have+過去分詞

　　與現(xiàn)在事實相反過去式should/would+動詞原形

　　與將來事實相反1、過去式should/would+動詞原形

　　2、should+動詞原形should/would+動詞原形

　　3、were to+動詞原形should/would+動詞原形

　　虛擬條件句的倒裝：

　　虛擬條件句的從句部分如果含有were, should, 或had, 可將if省略，再把were, should或had移到從句句首，實行倒裝。

　　如：Were they here now, they could help us.=If they were here now, they could help us.

　　Had you come earlier, you would have met him=If you had come earlier,

　　you would have met him.

　　Should it rain, the crops would be saved.=Were it to rain, the crops would

　　be saved.

　　注意：在虛擬語氣的從句中，動詞“be”的過去時態(tài)一律用“were”，不用was，即在從句中be用were代替。

　　如：If I were you, I would go to look for him. 如果我是你，就會去找他。

　　If he were here, everything would be all right. 如果他在這兒，一切都會好的。

　　初中虛擬語氣知識點拓展：

　　一、條件狀語從句

　　1、與現(xiàn)在事實相反若與現(xiàn)在事實相反，虛擬語氣的條件從句的謂語用過去式(be通常用were)，主句謂語用“should (would, could, might)+動詞原形”。如：If I were you, I would take an umbrella. 如果我是你，我會帶把傘。(事實上我不可能是你)If I knew her number I could ring her up. 要是我知道她的電話號碼，我就可以給她打電話了。(事實上我不知道)

　　2、與過去事實相反若與過去事實相反，從句：主語+had done ， 主句：主語+should/would/could/might+have done　，例如：If I'd left sooner，I'd have been on time. 要是我早點動身，我就準時到了。(但我動身太遲了)If I had got there earlier, I should/could have met her. 如果我早到那兒，我就會見到她。 (事實：去晚了)

　　3、與將來事實相反

　　從句：

　?、賗f+主語+were to do

　　②if+主語+did/were

　?、踚f+主語+should+do

　　主句：①主語+should/would/could/might+do

　　②主語+should/would/could/might+do

　?、壑髡Z+should/would/could/might+do

　　例如：If he went，would you go too? 如果他去，你也去嗎?(大概他不會去)

　　If he should come here tomorrow, I would talk to him.

　　如果他明天來這兒的話，我就跟他談談。 (事實：來的可能性很小)

　　注意與說明：對于與將來事實相反的情形，請注意以下幾點：

　　一是這里說的與將來事實相反，實為對將來情況的推測;

　　二是此用法中的條件從句謂語除用過去式外，有時也用“should+動詞原形”(表示可能性極小，常譯為“萬一”)或“were to+動詞原形”(表示與將來事實相反的假設);

　　三是當條件從句使用“should+動詞原形”這樣的謂語時，主句謂語除可用“should (would, could, might)+動詞原形”這樣的虛擬語氣外，也可用陳述語氣或祈使語氣。

　　如：I should see him, I'll tell him. 萬一我見到他，我就告訴他。

　　If it should rain tomorrow, don’t expect me. 萬一明天下雨，就別等我了。

　　二、wish 后賓語從句

　　1、表示與現(xiàn)在事實相反的愿望，謂語動詞用過去式 。

　　例如：

　　I wish I had your brains. 　　我希望我有你那樣的頭腦。(事實：我根本比不上你)

　　2、表示與過去事實相反的愿望，謂語動詞：had+done

　　例如：I wish I had knownthe truth of the matter. 我希望我那時就知道這件事情的真相。(事實：那時還不知道)

　　3、表示將來難以實現(xiàn)的愿望，謂語動詞：

　　should/would(情態(tài)動詞) + 動詞原形

　　I wish I should havea chance again. 　　我希望我還能有一次這樣的機會。(事實：很難再有這樣的機會了)

　　常見考法

　　The volleyball match will be put off if it___.

　　A. will rain

　　B. rains

　　C. rained

　　D. is rained

　　答案：B。真實條件句主句為將來時，從句用一般現(xiàn)在時。

　　There was plenty o ftime. She___.

　　A. mustn't have hurried

　　B. couldn't have hurried

　　C. must not hurry

　　D. needn't have hurried

　　答案：D。needn't havedone. 意為"本不必"，即已經(jīng)做了某事，而時實際上不必要。 Mustn't have done用法不正確，對過去發(fā)生的事情進行否定性推斷應為couldn't have done,“不可能已經(jīng)”。must not do不可以(用于一般現(xiàn)在時)

　　典型例題：

　　_____to do the work, I should do it some other day.

　　A. If were I

　　B. I were

　　C. Were I

　　D. Was I

　　答案：C. 在虛擬條件狀語中如果有were, should, had這三個詞，通常將if省略，主語提前，變成were, should, had+主語的形式。

　　看了“初中虛擬語氣知識點”的還看了：

1.虛擬語氣的用法總結歸納

2.語法小點——虛擬語氣

3.虛擬語氣wish的常見用法

4.初中英語語法知識點總結

5.初中英語知識點講解