四六級常考語法精講虛擬語氣ppt課件

1、四六級?？颊Z法之虛擬語氣四六級?？颊Z法之虛擬語氣1. 表示如今表示如今/過去過去/未來情況的虛擬條件句未來情況的虛擬條件句v虛擬條件句主要有三種構(gòu)造：1)表示與如今情況相反：主句謂語用“would / could / might +動(dòng)詞原形，從句謂語用“動(dòng)詞的普經(jīng)過去時(shí)動(dòng)詞be的過去式一概用were。If I were you, I would not accept his offer.If I had time, I would certainly go to the cinema with you.2) 表示與過去情況相反：主句謂語用“would / could / might + hav

2、e +過去分詞，從句謂語用過去完成時(shí)。If I had got up a little earlier, I wouldnt have missed the train.If I had been more careful, I might have passed that exam.3) 表示與未來情況相反：主句謂語用“would / could / might +動(dòng)詞原形，從句謂語用“were +動(dòng)詞不定式或“should +動(dòng)詞原形。If I were to do the job, I would not be able to have enough time to study.If i

3、t should rain tomorrow, I would not go out with you.2. 虛擬條件句銜接詞虛擬條件句銜接詞if的省略的省略v假設(shè)虛擬條件句的從句中含有were, had, should, could等詞時(shí)，可以省略銜接詞if，但這時(shí)必需把were, had, should, could等詞移到主語前面，構(gòu)成倒裝。這種句型主要用于書面方式。Were I to do the job, I would finish doing it within two weeks.Had it not been for his help, we couldnt have arr

4、ived there on time.Should it rain tomorrow, I would stay at home.3. wish后賓語從句中的謂語構(gòu)成后賓語從句中的謂語構(gòu)成v動(dòng)詞wish后的賓語從句表示未實(shí)現(xiàn)的或不能夠?qū)崿F(xiàn)的愿望，其賓語從句中的謂語動(dòng)詞要用虛擬語氣，有以下三種構(gòu)成方式。1) 表示如今不能夠?qū)崿F(xiàn)的愿望，賓語從句中的謂語動(dòng)詞用普經(jīng)過去時(shí)。be的過去式為were。I wish I had enough money to buy a car.I wish I were as young and energetic as you.2) 表示過去未能實(shí)現(xiàn)的愿望，賓語從句中的

5、謂語動(dòng)詞用過去完成時(shí)had +過去分詞或“would / could + have +過去分詞 。I wish I hadnt made such a mistake.I wish I could have done it better.3) 表示未來不能夠?qū)崿F(xiàn)的愿望，賓語從句中的謂語動(dòng)詞用“would / should (could, might) +動(dòng)詞原形。I wish I would not get old.I wish I could travel around the world one day.4. 某些動(dòng)詞后的賓語從句中謂語動(dòng)詞某些動(dòng)詞后的賓語從句中謂語動(dòng)詞要用虛擬語氣要用虛擬

6、語氣v在一些動(dòng)詞后面的賓語從句中，謂語動(dòng)詞要用虛擬語氣。這時(shí)，謂語動(dòng)詞用動(dòng)詞原形或should +動(dòng)詞原形。這類動(dòng)詞普通表示命令，要求，決議，建議，主張等概念，主要有：advise, ask, command, decide, demand, desire, direct, insist, move, order, propose, recommend, request, require, suggest,等。The workers demanded that their wages (should) be raised by 10 per cent.The teacher decided t

7、hat you do the experiment first.5. 某些名詞后的表語從句和同位語從某些名詞后的表語從句和同位語從句中謂語動(dòng)詞要用虛擬語氣句中謂語動(dòng)詞要用虛擬語氣v在一些名詞后面的表語從句和同位語從句中，謂語動(dòng)詞要用虛擬語氣。這時(shí)，謂語動(dòng)詞用動(dòng)詞原形或should +動(dòng)詞原形。這類名詞普通表示命令，要求，決議，建議，主張等概念，主要有：advice, idea, instruction, motion, order, plan, proposal, recommendation, request, requirement, suggestion,等。My suggestion

8、is that we (should) send for a doctor immediately.He gave the order that they (should) do the experiment again.6. 錯(cuò)綜時(shí)間條件句錯(cuò)綜時(shí)間條件句v條件從句表示的動(dòng)作和主句表示的動(dòng)作，有時(shí)發(fā)生的時(shí)間是不一致的.如從句是對過去情況的假設(shè)，而主句能夠是對如今正在進(jìn)展情況的假設(shè)。 這種句子稱為錯(cuò)綜時(shí)間條件句.If the weather had been more favorable, the crops would be growing still better.7. 某些主語從句中的謂語

9、動(dòng)詞要某些主語從句中的謂語動(dòng)詞要用虛擬語氣用虛擬語氣v某些表示命令，要求，決議，建議，主張以及“重要性和“緊迫性等概念的主語從句中謂語動(dòng)詞要用虛擬語氣。這時(shí)，謂語動(dòng)詞用動(dòng)詞原形或should +動(dòng)詞原形。這類主語從句普通由 “It is (was) + 描畫詞過去分詞 + that引導(dǎo)的從句構(gòu)成。該構(gòu)造中，常用的描畫詞主要有：advisable, appropriate, desirable, essential, imperative, important, necessary, obligatory, proper, urgent, vital等；常用的過去分詞主要有：arranged,

10、decided, demanded, desired, ordered, proposed, recommended, requested, suggested等。It is necessary that you (should) stop smoking so heavily.It is arranged that you (should) enter for this competition.8. as if / though引起的從句引起的從句v當(dāng)as if / though引起的從句所表達(dá)的內(nèi)容完全與實(shí)踐情況相反或者純粹是一種假設(shè)時(shí)，通常要用虛擬語氣。假設(shè)從句表示與如今的現(xiàn)實(shí)相反，謂語

11、動(dòng)詞用普經(jīng)過去時(shí)；假設(shè)從句表示與過去的現(xiàn)實(shí)相反，謂語動(dòng)詞用過去完成時(shí)；假設(shè)從句表示與未來的現(xiàn)實(shí)相反，謂語動(dòng)詞用would (might, could) + 動(dòng)詞原形；They talked as if they had been friends for years.I remember the whole thing as if it happened yesterday.It looks as if it might rain.Note: 假設(shè)as if / though引起的從句所表達(dá)的內(nèi)容被看作是現(xiàn)實(shí)或者有能夠是真實(shí)的，那么要用陳說語氣。It seems as if it is goin

12、g to rain.The meat tastes as if it has already gone bad.大9. lest, for fear that和和 in case引起的從句引起的從句v當(dāng)lest, for fear that和 in case表示“以免，以防，生怕，惟恐等時(shí)，在它們引起的從句中，謂語動(dòng)詞常用should + 動(dòng)詞原形。He ran away lest he should be seen.Hes working hard for fear that he should fall behind.He left early in case he should miss

13、 the last train.10. If only引出的從句引出的從句vIf only引出的從句用以表達(dá)感慨性的愿望，常譯為“要是就好了。If only從句經(jīng)常省略結(jié)果主句，且主要用在虛擬語氣中，即從句的謂語動(dòng)詞用普經(jīng)過去時(shí)表示如今或未來不能夠?qū)崿F(xiàn)的愿望，或用過去完成時(shí)表示過去沒有實(shí)現(xiàn)的愿望。If only the rain would stop.If only Id listened to my parents.Note: if only引出的句子偶爾也可運(yùn)用陳說語氣，但考生須留意的是，在各類測試中普通都以用虛擬語氣為正確答案。11. would ratherthat引出的從句引出的從句

14、vwould rather意為“寧愿，接從句時(shí)常省略關(guān)系代詞that。would rather后的從句要用虛擬語氣，即從句謂語動(dòng)詞用普經(jīng)過去時(shí)表示如今或未來的愿望，用過去完成時(shí)表示與過去現(xiàn)實(shí)相反的愿望。Id rather you told me the truth.I would rather you came tomorrow than today.Id rather you hadnt told me about it.12. It is (about/high) time (that) 句型句型v該句型表示“早該做，其后的定語從句中的謂語動(dòng)詞要用虛擬語氣表示。在測試中從句的謂語動(dòng)詞用普經(jīng)

15、過去時(shí)。It is time that we went to bed.It is high time that somebody taught you to behave yourself.13. 表示猜測的幾種不同的方法及意義v一些情態(tài)動(dòng)詞與動(dòng)詞的完成式連用可以表示對過去情況的猜測或者未實(shí)現(xiàn)的能夠性。1) could have + 過去分詞A. 表示對過去能夠發(fā)生的事情的推測，意為，“能夠做了某事。He couldnt have seen her yesterday.They could have lost their way.B. 表示某事在過去本有能夠發(fā)生，但現(xiàn)實(shí)上并未發(fā)生，意為，“本可

16、以做某事。We could have started a little earlier.I could have killed her. It was a narrow escape.v2) may (might) have + 過去分詞A. 表示對過去情況的推測，意為，“能夠已做某事。He may have heard the news.I might have come to a wrong conclusion.B. 表示一種未實(shí)現(xiàn)的能夠性，即本可以做某事，而實(shí)踐上并沒有做，有時(shí)含有埋怨的口吻。It was a narrow escape. You might have killed y

17、ourself.A lot of men died who might have been saved.v3) must have + 過去分詞表示邏輯上的必然性，即按照某些景象推斷過去一定發(fā)生過的某事。She must have made a big mistake.The city at one time must have been prosperous, for it enjoyed a high level of civilization.v4) neednt have + 過去分詞表示過去不用做某事，但曾經(jīng)做了，即本可不用做某事。You neednt have woken me u

18、p. I dont have to go to work today.He neednt have watered the flowers, for it is going to rain.5) should / ought to have + 過去分詞表示過去應(yīng)該做某事而實(shí)踐上沒有做。You should / ought to have done what your parents told you. (But you failed to do it.)You should / ought to have been more careful. (But you werent.)v6) shouldnt / oughtnt to have + 過去分詞表示過