1 語氣(mood) 語氣是動(dòng)詞的一種形式，表示說話人對某一行為或事情的看法和態(tài)度。
2 語氣的種類 �、�、陳述語氣：表示動(dòng)作或狀態(tài)是現(xiàn)實(shí)的、確定的或符合事實(shí)的，用于陳述句、疑問句和某些感嘆句。如： �、賂here are two sides to every question.每個(gè)問題都有兩個(gè)方面。 ②Were you busy all day yesterday?昨天一整天你都很忙嗎？ �、跦ow good a teacher she is!她是多好的一位老師啊！ �、�、祈使語氣：表示說話人對對方的請求或命令。如： �、貼ever be late again!再也不要遲到了。 �、贒on’t forget to turn off the light.別忘了關(guān)燈。 �、�、虛擬語氣：表示動(dòng)作或狀態(tài)不是客觀存在的事實(shí)，而是說話人的主觀愿望、假設(shè)或推測等。如： �、買f I were a bird, I could fly in the air.如果我是一只小鳥，我就能在空中飛行。 ②I wish I could pass the examination.我希望我能通過考試。 �、跰ay you succeed!祝您成功！ 虛擬語氣在語法里算得上是個(gè)難點(diǎn)。讓我們就從最簡單的開始吧。
第二部分：簡單句中的虛擬語氣
一、情態(tài)動(dòng)詞的過去式用于現(xiàn)在時(shí)態(tài)時(shí)，表示說話人的謙虛、客氣、有禮貌、或委婉的語氣，常用于日常會(huì)話中。如： ⑴.Would you be kind enough to show me the way to the post office?請你告訴我去郵局的路好嗎？ �、�.It would be better for you not to stay up too late.你最好別熬夜到很晚。
二、表祝愿。 1、常用“may+動(dòng)詞原形”表示祝愿，但愿，此時(shí)may須置于句首（多用于正式文體中）。 �、�、May good luck be yours!祝你好運(yùn)！ �、�、May you be happy!祝你快樂！ �、�、May you do even better!祝你取得更大成就！ �、�、May you have a good time. 祝愿你玩的痛快。 �、�、May the friendship between us last long. 祝愿我們的友情天長地久。 �、�、May you be happy. (注意那個(gè)be ) 祝你幸福。 2、用動(dòng)詞原形。例如： (1).Long live the people! 人民萬歲！ (2).“God bless you,”said the priest.牧師說：“愿上帝保佑你！” (3).Have a good journey! 祝愿你旅途愉快！
三、表示強(qiáng)烈愿望。（該類型虛擬語氣謂語僅用動(dòng)詞原形，第三人稱單數(shù)也不加“s”） (1).God save me. (2).Heaven help us.
四、表命令 1.命令虛擬語氣只能用在第二人稱(you)，而且通常省略主語(也就是you)。 2.句子尾通常加上感嘆號(hào)：！ 3.虛擬語氣動(dòng)詞用一般現(xiàn)在時(shí)態(tài)(Simple Present)，如：work, be , go 4.否定形式的命令語氣，可用助動(dòng)詞do，加上not。 (1). Work ! (2). Work harder ! (3). Be more alert ! (虛擬語氣動(dòng)詞Be) (4). You go out ! (5). Do not work so hard. (do not 表示否定的虛擬語氣) (6). Don't be afraid. (口語中常用don't 代替do not)
五、在一些習(xí)慣表達(dá)中。如： (1).You’d better set off now.你最好現(xiàn)在就出發(fā)。 (2).I’d rather not tell you the secret.我情愿不告訴你這個(gè)秘密。
第三部分：名詞性從句中的虛擬語氣
第一節(jié)：賓語從句(Subordinate Clasue)中的虛擬語氣
一、在動(dòng)詞wish后的賓語從句中的虛擬語氣 在動(dòng)詞wish后的賓語從句中的虛擬語氣，常省去賓語從句的引導(dǎo)詞that。
一）、對現(xiàn)在情況的虛擬（與現(xiàn)在的事實(shí)相反）：
從句用過去式或過去進(jìn)行式(時(shí)間上是同時(shí)的)。其句子結(jié)構(gòu)為：賓語從句的謂語be和were(was)，實(shí)義動(dòng)詞用過去式。例： 1. I wish (that可省略,下同)I knew the answer to the question.(wish, 動(dòng)詞過去式knew)我希望知道這個(gè)答案。(事實(shí)上是不知道) 2. I wish it were spring in my hometown all the year around.(wish, were)但愿我的家鄉(xiāng)四季如春。(事實(shí)上不可能) 3. I wish I were a bird.(wish, were)但愿我是只小鳥。(事實(shí)上不可能) 4. When she was at the party,she wished she were at home.(wished,過去虛擬動(dòng)詞were)(事實(shí)上并不在家) 5. Now that he is in China, he wishes he understood Chinese.(wishes,過去虛擬動(dòng)詞understood) 現(xiàn)在他在中國，他希望能懂得中文。(事實(shí)上并不懂) 6. When we begin the trip, they will wish they were with us.(will wish,過去虛擬動(dòng)詞were)(事實(shí)上并不和我們在一起)
二）、對過去情況的虛擬（和過去的事實(shí)相反）：
用wish表示對過去事情的遺憾。其句子結(jié)構(gòu)為：賓語從句的謂語用過去完成時(shí)，或would, could, might+現(xiàn)在完成時(shí)。例： 1. I wish (that可省略，下同)I hadn't wasted so much time. 我后悔不該浪費(fèi)這么多時(shí)間。(事實(shí)上已浪費(fèi)了) 2. He wishes he hadn't lost the chance. 他真希望沒有失去機(jī)會(huì)。(其實(shí)已失去) 3. We wished he had spoken to us. (wished，had + spoken)(事實(shí)上他并沒同我們講) 4. I wish you had called earlier. (wish, had + called)(事實(shí)上已遲了) 5. They will wish they had listened to us sooner. (will wish,had + listened)(事實(shí)上并不如此) 例題分析：I wish I ______ longer this morning, but I had to get up and come to class. A. could have slept B. slept C. might have slept D. have slept 動(dòng)詞wish后面接從句，表達(dá)不可能實(shí)現(xiàn)或與事實(shí)相反的情況時(shí)，謂語動(dòng)詞要用虛擬語氣，即用過去式（表示現(xiàn)在發(fā)生的動(dòng)作）或過去完成式（表示過去發(fā)生的動(dòng)作）。本題后半句謂語動(dòng)詞have用的是過去時(shí)had to get up and come, 所以前面要用過去完成時(shí)表示過去發(fā)生的動(dòng)作。所以, 選項(xiàng)A)could have slept是答案
三）、對將來情況的虛擬(表示將來的主觀愿望)：
從句動(dòng)詞"would/should/could/might + 動(dòng)詞原形"(時(shí)間上較后)(請注意：主句和從句的主語不相同)。用wish表示對將來事情的愿望。例： 1. I wish it would stop raining.(虛擬動(dòng)詞would+動(dòng)詞原形stop) 我希望雨能停止。(事實(shí)上雨還在下著呢) 2. I wish you would be quiet.(would + be) 我希望你安靜一些。(事實(shí)上那家伙還在吵著呢) 3. You wished she would arrive the next day.(would + arrive) 你希望她第二天會(huì)到。(事實(shí)上她還沒到) 4. I wish she would change her mind.(would + change) 我希望她會(huì)改變主意。(呵呵，女孩子可沒那么容易就改變主意喔) 5. He will wish we would join him the following week.(would + join) (只是希望我們和他在一起，實(shí)際上還沒在一起)
四）、注意：
1.如果將wish改為過去式wished, 其后that 從句中的動(dòng)詞形式不變。例如： I wished I hadn't spent so much money. 我要是那時(shí)沒有花掉那么多錢就好了。 2. 如果that 從句中用would , 一般表示對現(xiàn)狀不滿或希望未來有所改變或請求 I wish he would answer my letter. I wish prices would come down. I wish you would help me. I wish you would stop asking silly questions.
二、在表示建議、命令、要求、忠告等動(dòng)詞的后面的賓語從句中的虛擬語氣
由于這些動(dòng)詞本身隱含說話者的主觀意見，認(rèn)為某事應(yīng)該或不應(yīng)該怎樣，這些詞語后面的“that”從句應(yīng)用虛擬語氣，且均以“should+動(dòng)詞原形”表示這種語氣，但事實(shí)上“should”常被省略，故此從句中謂語動(dòng)詞用原形，常用的此類動(dòng)詞有： 表示“要求”的：ask, desire, request, demand, require, beg 表示“提議、勸告、建議”的：move, prpose, suggest, recommend, advise, vote 表示“決定、命令”的：decide, order 表示“主張”的：maintain, urge 表示“同意、堅(jiān)持”的：consent, insist
例如： 1.The doctor suggested that he (should) try to lose his weight. 2.He insisted that we (should ) tell him the news. 3.When I suggested that he try shaving cream, he said, “The razor and water do the job. ”(當(dāng)我建議他用刮胡膏時(shí)，他說“剃刀和水就行了”。) 4.He pursued various theories for several days until I suggested we take the toy apart to see how it did work. (他費(fèi)了幾天功夫?qū)ふ依碚摳鶕?jù)，直到我建議拆開看看它是如何轉(zhuǎn)動(dòng)的。) 5.One can suggest that students should spend two or three years in an English?speaking country. (我們建議學(xué)生應(yīng)在說英語的國家呆上兩三年。)
在表示命令、建議、要求等一類動(dòng)詞后面的從句中虛擬語氣很普遍，其結(jié)構(gòu)如： order, suggest, propose, require, demand, request, insist, command, insist +... (should) do 6.I suggest that we (should) hold a meeting next week. 7.He insisted that he (should ) be sent there. 但注意：在insist 后的從句中, 如果是堅(jiān)持自己, 用陳述語氣, 堅(jiān)持別人做什么事情, 用虛擬語氣. 8.she insists that she is right. 9.she insisted that I should finish the work at once. 或者說，suggest, insist不表示建議或堅(jiān)持要某人做某事時(shí)，即它們用于其本意暗示、表明、堅(jiān)持認(rèn)為時(shí)，賓語從句用陳述語氣。 10.The guard at gate insisted that everybody obey the rules.
判斷改錯(cuò): (錯(cuò))11. You pale face suggests that you (should) be ill. (對)12. Your pale face suggests that you are ill. (錯(cuò))13. I insisted that you ( should) be wrong. (對)14. I insisted that you were wrong. 例題分析：15.It is politely requested by the hotel management that radios ______ after 11 o'clock at night. A. were not played B. not be played C. not to play D. did not play
全句意思是：“旅館管理部門懇請客人晚上11點(diǎn)后不要打開收音機(jī)”。句中的謂語動(dòng)詞request（請求）所引出的從句應(yīng)當(dāng)用虛擬語氣，即動(dòng)詞原形或“should＋動(dòng)詞原形”。本句的主語從句中，主語radio是謂語動(dòng)詞play 的客體，謂語應(yīng)當(dāng)用被動(dòng)語態(tài)。所以，答案是C) not be played。在上述這類句子中不能用動(dòng)詞過去時(shí)形式表示虛擬語氣，所以A)不正確。選項(xiàng)B) not to play是動(dòng)詞帶to的不定式，不能在句中作謂語。選項(xiàng)D)did not play也是動(dòng)詞play的過去時(shí)形式，同樣不能在本句中作為虛擬語氣來使用。而且，它是主動(dòng)語態(tài)形式，而本題要用被動(dòng)語態(tài)。
練習(xí)： 16). The chairman requested that . �。跘］the members studied more carefully the problem �。跙］the problem was more carefulnessly studied �。跜］with more carefulness the problem could be studied �。跠］the members study the problem more carefully 17). The committee recommends that the matter at the next meeting . ［A］would be discussed �。跙］will be discussed �。跜］be discussed ［D］may be discussed 18). The doctor insisted that his patient . �。跘］that he not work too hard for three months �。跙］take it easy for three months �。跜］taking it easy inside of three months �。跠］to take some vacations for three months
三、在expect, believe, think, suspect等動(dòng)詞的否定或疑問形式后的賓語從句中的虛擬語氣
在expect, believe, think, suspect等動(dòng)詞的否定或疑問形式后的賓語從句中，我們經(jīng)常用“should＋動(dòng)詞原形(或完成形式)”，表示驚奇，懷疑，不滿等。
I never thought that he should be such a brave young soldier. 我們從來沒想到他是個(gè)如此勇敢的小戰(zhàn)士。
練習(xí)： 1) that the time will soon be ripe for intervention in Iran，they would be faced by a large army? �。跘］It is believed �。跙］Should they believe �。跜］They would believe �。跠］If they would believe 2) I think it advisable that he for Tokyo soon. �。跘］will leave �。跙］may leave �。跜］leave ［D］leaves
四、would rather ， would sooner，had rather， would (just) as soon ，would prefer之后的賓語從句中的虛擬語氣
would rather , would sooner, had rather, would (just) as soon，would prefer（希望）也用來表達(dá)主觀愿望，它們之后的賓語從句中需用虛擬語氣。謂語動(dòng)詞用過去式表示現(xiàn)在或?qū)恚眠^去完成式表示與過去事實(shí)相反。表示”寧愿做什么”或"對過去做的事的懊悔"。 (1).I would rather he came tomorrow than today. (2).John would rather that she had not gone to the party yesterday evening. (3).Don' t live in the world, I would rather( I would just as soon) you die. (4).I would rather you go tomorrow. (5).I would rather everything hadn' t happened in the past. (6).The manager would rather his daughter did not work in the same office.經(jīng)理寧愿她女兒不與他在同一間辦公室工作。 (7).To be frank，I'd rather you were not involved in the case.坦率地說，我希望你不要卷入這件事。 (8).You don't have to be in such a hurry.I would rather you went on business first.你沒有必要這么著急，我寧愿你先去上班。 (9).I'd rather you didn't make any comment on the issue for the time being.我倒希望你暫時(shí)先不要就此事發(fā)表意見。 (10).Frankly speaking ，I'd rather you didn't do anything about it for the time being.坦白地說，我寧愿你現(xiàn)在對此事什么也不要做。 (11).Wouldn't you rather your child went to bed early？為什么你不愿讓你的孩子早點(diǎn)上床呢？ (12).I would just as soon you had returned the book yesterday.我真希望你昨天把這本書還了。 注：①若某人愿自己做某事，would rather后用動(dòng)詞原形 I would rather stay at home today. ②would rather...than...中用動(dòng)詞原形 I would rather stay at home than go out today.
五、“had hoped”后的賓語從句中的虛擬語氣
用“had hoped”表示原來希望做到而實(shí)際上未能實(shí)現(xiàn)的事情，其賓語從句的謂語用“would+動(dòng)詞原形”。
I had hoped that she would go to the U.S. and study there, but she said she liked to stay in China.我原本希望她到美國去念書，但她說她喜歡留在中國。
第二節(jié)：主語從句中的虛擬語氣
一、“It is (was)+形容詞（或過去分詞）+that……”結(jié)構(gòu)中的虛擬語氣
在形如“It is (was)+形容詞（或過去分詞）+that……”結(jié)構(gòu)中，使用某些表示愿望、建議、請求、命令、可能、適當(dāng)、較好、迫切、緊近、重要等形容詞后的主語從句的謂語也用虛擬語氣。其表達(dá)形式為should ＋動(dòng)詞原形或省略should直接用動(dòng)詞原形（美國英語中省去should）
常用的形容詞：* natural (自然的), appropriate (適當(dāng)?shù)?,advisable (合適的), preferable (更可取的), better (更好的)* necessary (必須的), important (重要的), imperative (急需的), urgent (急迫的), essential (本質(zhì)的), vital (必不可少的)* probable (很可能的), possible (可能的)* desirable (極好的)advisable（合理的），compulsory（必須的），crucial（緊急的），desirable（理想的），essential（必要的），imperative（迫切的），incredible（驚人的），necessary（必要的），possible（可能的），strange（奇怪的），urgent（緊迫的）。
常用的過去分詞(Past Participle):* required (需要的), demanded (要求), requested (被請求的), desired (要求)* suggested (建議), recommended (推薦)* orderd (命令)
1. It is necessary that we (should 可省略,下同）have a walk now.(necessary, should + have) (表示有需要去散步) 2.It was necessary that we (should) make everything ready ahead of time.(necessary, should + make) (表示有必要事先做好準(zhǔn)備) 3. It is required that nobody (should) smoke here.(required, should + smoke) (表示要求不要在此抽煙) 4. It is important that every pupil (should) be able to understand therule of school.(important, should + be) (表示重要的是學(xué)生都能了解校規(guī)) 5. It's important that we (should) take good care of the patient.(important, should + take) (表示重要的是照顧好病人) 6. It is natural that she should do so. (形容詞natural, should+動(dòng)詞原形do) 7.It is essential that these application forms be sent back as early as possible.這些申請表應(yīng)盡早地寄回，這是很重要的。 8.It is vital that enough money be collected to fund the project.重要的是募集足夠的錢，為這個(gè)項(xiàng)目提供資金。 9.It is desired that we（should）get everything ready this evening.希望我們今晚一切都準(zhǔn)備就緒。 注：在上述所列形容詞后面用that引出的賓語從句中，謂語動(dòng)詞也要用虛擬語氣。 10.I don't think it advisable that Tom be assigned to the job since he has no experience.湯姆缺乏經(jīng)驗(yàn)，指派他做這項(xiàng)工作我認(rèn)為是不恰當(dāng)?shù)摹?BR> 二、在It is ＋名詞＋that…的主語從句中的虛擬語氣
在It is ＋名詞＋that的主語從句中，常用虛擬語氣，表示建議、命令、請求、道歉、懷疑、驚奇等。這類名詞 有：advice ，decision ，desire ，demand ，idea，motion ，order，pity ，preference ，proposal，recommendation ， requirement，resolution，shame，suggestion，surprise，wish，wonder等。 �、�、It is my proposal that he be sent to study further abroad.我建議派他去國外進(jìn)一步學(xué)習(xí)。
第三節(jié)：虛擬語氣用在表語從句或同位語從句中
當(dāng)某些表示建議、請求、命令等主觀意向的名詞作主語時(shí)，其后的表語從句或同位語從句需用虛擬語氣，其表達(dá)形式為should ＋動(dòng)詞原形或直接用動(dòng)詞原形。這類名詞常見的有： demand (要求), desire (請求),requirment (要求) advice (勸告), recommendation (建議),suggestion (建議) order (命令) necessity (必要地), preference (優(yōu)先) proposal (計(jì)劃), plan (計(jì)劃), idea (辦法)， recommendation以及plan，idea，resolution等。 We are all for your proposal that the discussion be put off.我們都贊成你提出的將討論延期的建議。 The suggestion that the mayor present the prizes was accepted by everyone.由市長頒發(fā)獎(jiǎng)金的建議被每個(gè)人接受。 ⑴、 The advice is that we (should 可省略，下同) leave at once. (名詞advice，should + leave) (表示加以勸告) �、�、 My idea is that we (should) get more people to attend the conference. (idea, should + get) (表示做出主意) ⑶、 I make a proposal that we (should) hold a meeting next week. (proposal, should + hold) (表示做出計(jì)劃)
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