1、步驟一：虛擬式的內容解析一三種語氣簡介式，又譯作“語氣”，是語法范疇，它是區別說話人以何種口氣說話的動詞形式，英語動詞有3種表示不同口氣的動詞形式：陳述式、祈使式和虛擬式。1. 陳述式。表示謂語動詞所表達的動作或狀態是符合客觀現實的，也就是說把動作或狀態當作事實表達出來，或提出一種看法。Flowers blossom in spring. The moon is peeping through the window at the sleepless girl. 2. 祈使式表示號召、命令、請求、勸告、警告、禁止等。Let us help you. Do drop in to see us. 3

2、. 虛擬式虛擬式，傳統譯作“虛擬語氣”，是專門表達“假設意義”及其他“非事實意義”的動詞形式，它表達的是懷疑、憂慮、推測、假設、想象或祝愿等。虛擬式有兩個形式，即be-型虛擬式和were-型虛擬式。Mother told me to put on my sweater lest I should catch cold. I wish I were a white cloud. 二虛擬式基本句型1. be-型虛擬式 be-型虛擬式是動詞原形表示的，即不管主語時什么人稱，動詞一律用原形，如I go, you go, he go或I be, you be, he be。如果動詞為被動態，則助動詞be

3、也一律用原形，如I be sent, you be sent, he be sent。因此，如果主語時復數，便顯示不出虛擬式與陳述式的區別：除了虛擬式be 與陳述式am / is / are/ was/ were有所區別外，其他動詞的be-型虛擬式只有在單數第三人稱主語之后才是有標記的。a) 用于表示命令、決定、建議等詞語之后的that-分句中b) 用在decide, decree, demand, insist, move(提議)，order, prefer, propose, recommend, request, require, suggest, vote等動詞之后的that-分句中。

4、He ordered that all the books be sent at once. c) 用在advisable, appropriate, desirable, essential, fitting, imperative, important, impossible, necessary, obligatory, proper等形容詞之后的that-分句中。It is essential that all the facts be examined first. d) 用在decision, decree, demand, instruction, order, requirem

5、ent, resolution等名詞之后的that-分句中。We were faces with the demand that this tax be abolished. 在這一用法中的be-型虛擬式能與“should+不定式”交替使用，也能與to-不定式交替使用。 He ordered that the books be sent at once. = He ordered that books should be sent at once. = He ordered that books to be sent at once.2) 用于由if, though等引導的分句中be-型虛擬式

6、能用于由if, though, whatever, lest, so long as等引導的分句中表示推測、讓步、防備等含義。If he be found guilty, John shall have the right of appeal. So long as a volume hold together, I am not disturbed as to its outer appearance.上述用法現在只限于正式書面語體，在非正式語體中通常用動詞陳述式或者用should/may+不定式。He hid himself in the bush lest he should be se

7、en.3) 用于某些公式化語句中be-型虛擬式用于某些公式化語句中可表示祝愿、詛咒、禁止等意義。Long live the Peoples Republic of China!God bless you!2. were-型虛擬式were-型虛擬式只是一種形式，即不管主語是什么人稱，動詞一律用were, 如I were, you were, he were; 如果動詞為進行體或被動態，其助動詞也一律用were, 如I were going, you were going, he were going, I were sent, you were sent, he were sent. 因此，we

8、re-型虛擬式只有出現在單數第三人稱主語之后，它才在形式上與陳述式區別開來。1）用于某些狀語分句中 were-型虛擬式常用于由if, if only, as if, as though, though引導的條件狀語和讓步狀語分句中，表示非真實的條件或讓步。 If I were you, I should wait till next year. 2) 由于某些名詞性分句中 were-型虛擬式常用于wish, would rather, suppose, imagine之后的that-分句中，表示一種臆想（通常是不可能發生的）情況。 I wish it were spring at the ye

9、ar round. 上述were-型虛擬式在第一、第三人稱單數主語之后可為was所取代。 但是，在if I were you句型中，通常傾向用were, 不用was。 另外在某些倒裝結構中只用were, 不用was。三虛擬式的使用1. 虛擬式在條件句中的使用 英語中的條件句一般有兩種：真實條件句和非真實條件句，虛擬式用在非真實條件句中。非真實條件句包括虛擬條件句、推測條件句和錯綜時間條件句。1）虛擬條件句 虛擬條件句可分為兩類：一類是敘述與現在事實相反的情況，一類是敘述與過去事實相反的情況。另外，還有一類用于推測將來的情況，也稱作推測條件句。條件從句結果主句與現在事實相反If I (we, y

10、ou, he, she, it, they)+動詞過去式（be動詞的過去式一律用were）I (we, you, he, she, it, they)+would+動詞原形與過去事實相反If I (we, you, he, she, it, they)+動詞分詞I (we, you, he, she, it, they)+would+ have+過去分詞與將來時間相反A式：一般過去時B式：were+不定式C式：should+動詞原形would (should)+ 動詞原形 以下與現在事實相反：He wouldnt feel so cold if he were indoors. If its

11、and ans were pots and pans, thered be no work for tinkers hand.以下與過去事實相反If we hadnt made adequate preparations, the conference wouldnt have been so successful.以下推測將來If he were here this evening, we would be happy. If it should rain again, what else could I do? 虛擬條件句中的謂語可用進行時，表示“如果正在”等，主句中的謂語仍用would（

12、或might, should, could），并根據情況選用時態。If she were living a hard life, he should be responsible for it. 條件句通常放在主句前，但也可以放在主句后，有時也可放在句中。If you would marry me, all the property would be yours. All the property would be yours if you would marry me.All the property, if you marry me, would be yours. 條件句中有were,

13、had, should, could時，可以省略if, 而把were, had, should, could放在主語前，用倒裝結構。這種用法主要用于書面語中。Were it necessary, I might resign. 虛擬語氣中的主句通常是陳述句，但也可以是疑問句，感嘆句或祈使句。If she had everything, would she be happy?If he had married Alice, how happy he would have been！if you were man enough, dont give up! could have+過去分詞也可以用于

14、虛擬條件句中，這時的could 是情態動詞，表示“能夠”，相當于had been able to.If I could have earned enough money, I should have traveled over the world. Note: 1) 在同一個句子中，不能一部分表示真實條件，另一部分表示非真實條件，不然就會破壞句子的一致性。If he is here, he would not let the matter end this way. (誤)If he were here, he would not let the matter end this way. (正

15、)2）條件從句中不可用would,否則就是語病。If he would have come yesterday, I should have told him. (誤)If he had come yesterday, I should have told him. (正) 但如果表示某種感情，條件從句也可用would, 相當于be willing to, 這常表示說話人不相信主語有這種愿望。If she would do it for me, I should be very much obliged. 2. 錯綜時間條件句 在錯綜時間條件句中，虛擬條件從句和主句動作發生的時間不一致，因此，

16、主句和從句的謂語動詞要根據各自所指的不同時間選用適當的虛擬語氣形式。 Had I taken my umbrella with me when I came out his morning, I should not be wet now. 如果我早上出門時帶了傘，現在就不會淋濕了。（過去現在） If I were you, I wouldnt have missed the film last night. (現在過去) If Mary should arrive today, she must have started three days ago. 如果瑪麗今天到達的話，那她一定在3天前

17、就動身了。（將來過去）Note：如果條件句作賓語從句，其動詞形式不受主句謂語動詞的影響。I often tell her that if she had made another try, she might have been successful. 我經常同她說，要是她再試一次的話，她可能會成功了。（過去）3. A wise man wouldnt have done that無“條件”的虛擬語氣句子這里的所謂無“條件”，指的是句子表層沒有通常使用的if或I wish 等引起的表示條件的句子，但其深層結構或是上下文中還是有條件的。這種條件可以用介詞、形容詞、名詞、代詞、連詞、動詞、分詞、不

18、定式、定語從句或上下文等表示出來，用的是跳層或間接的方式。表示無“條件”的詞有with, without, but for, or, but, otherwise, even, in case of, what if (如果將如何)等。這種句子往往是有主句而無從句。I would do so in your place.。（介詞短語）Doing your best, you would be scolded all the same.（介詞短語，=if you did your best）Left to himself, he would get lost in the woods.（分詞短語

19、，=if he were left to himself）Not to be moved by it would require a heart of stone. But for her guidance, we should fail. (同現在事實相反)Bur for her guidance, we should have failed. (同過去事實相反)4. 含蓄條件句有些句子中，沒有任何表示虛擬語氣的詞、短語或從句，但仍要用虛擬語氣。這時，要么是省略了表示虛擬語氣的部分，要么隱含的上下文中，稱為含蓄條件句。I would do anything for me. (if I cou

20、ld)She might have refused to answer. (I you had asked her) 注意 but + 表示條件的結構：would +動詞原形but (except) + 現在時陳述句（陳述語氣）表示同現在事實相反的假設would have + 過去分詞but (except) + 過去時陳述句（陳述語氣）表示同過去事實相反的假設I would have gone with her but I was too busy. 四假設意義表示法綜述 1. 用動詞的過去時形式表示假設意義 用動詞的過去時形式表示假設意義常用于以下結構1） It is (high, abo

21、ut) time (that)It is time we went to bed.It is high time that we were off. 這種結構中的過去式也可改為should+動詞原形（用should時，不能將其省略），但不如用過去式普通。It is about time we should go to bed. It is quite time she should wash her clothes. 2) I would rather / sooner (that) you / he / theya) 接動詞原形，指現在或將來時間，表示一種主觀愿望或選擇 Id rather

22、do it today. b) 接不定式完成式，表示過去的某種選擇不恰當 Id rather not have told her the news. She is such a gossip. c) 接從句，用虛擬語氣，為一般過去時，表示一個現在或將來的愿望；用過去完成時，表示一個過去的愿望。 Id rather you paid the money yourself. (現在) I would sooner she painted the wall green next time. (將來)3）if only 和 would that 后用虛擬語氣 謂語動詞用一般過去時表示現在沒有實現的愿望

23、，用過去完成時表示過去沒有實現的愿望，常譯為“要是就好了” If only she had known where to find you. Would that I could fly. 4）He behaves as if / as though He behaves as if he owned this place. 在though, if (=though), so long as, although, even if, even though, whether, whatever, wherever, whoever, however, whichever, no matter what (who, how)等強式連接代詞或副詞引導的讓步狀語從句中用虛擬語