1、 第九講 情態動詞和虛擬語氣一、情態動詞考點透析1can (could)，be able to。can 只有現在式 can 和過去式 could 兩種形式， be able to 可用于現在式、過去式、將來時、完成時。要表示“能夠做某事，可用 can 或 be able to，但假設要說過去確實運用了某種能力做成了某件事情，就只能用 was/were able to ，表將來具備的能力只能用will/shall be able to。(1)If you study hard，you will be able to express freely in English in three month

2、s.(2)The fire spread through the hotel very quickly but everyone was able to getout.2could 是 can 的過去式，但是在很多情況下，特別是在口語中，它表示語氣的委婉。因此，用 could 提問時，不能用 could 回答，而要用 can 或 may。would，might 用于疑問句時也表委婉語氣，回答時應該用 will，may。(1)Could I borrow your dictionary?Yes，of course you can.(2)Could I call you by the first

3、name?Yes，you may.(3)Would you be so kind as to explain the word?Yes，I will.What is it?3may/might，can/could 都可表示可能，但 may/might 不能用于問句，can/could 用于否認句、疑問句、感嘆句，表示驚異、懷疑，一般不用于肯定句。如果用于肯定句，如此表示偶爾發生某事的可能，或某人某物一時的特點。(1)Are you coming to Jeffs party?Im not sure.I might go to the concert instead.(2)Where can M

4、r.Li be?Sorry，I dont know.You can go to ask Mr.Zhang.He may help you.(3)Mr.Bush is on time for everything.How can it be that he was late for the openingceremony?(4)We enjoy good weather in January，but sometimes it can be terribly cold.4must 表推測用于肯定句，其否認式要用 cant。對現在表示推測：must do；cant do對正在進展的動作表示推測：mu

5、st be doing；cant be doing對過去表示推測：must have done；cant/couldnt have done(1)There were already five people in the ca，r but they managed to take me aswell.It couldnt have been a comfortable journey.(2)Jack cant have arrived yet，otherwise he would have telephoned me.(3)Put on more clothes，you must be fee

6、ling cold with only a shirt on.(4)I didnt hear the phone.I must have been asleep.5情態動詞完成式的意義。can/could have done過去可能做過，過去本來可以做某事但沒有做must have done 過去一定做過may have done 可能已經做過，本來可以做但沒做1 / 5 might have done 過去可能做過，過去本來可以做但沒做cant/couldnt have done 過去不可能做過某事should (not)have done過去本該(不該)做，但卻沒做(做了)neednt h

7、ave done 過去本來沒必要做，但卻做了(5)I would rather not have blamed him because he was a child after all.6關于 should 的主要用法。2 / 5 5We _ (not) have bought so much food now that Suzie wont be with usfor dinner.6One of our rules is that every student_wear school uniform while atschool.7Im going to Europe on vacation

8、 together with John if I _ find the money.8You have to believe in yourself.No one else will, if you dont.I _ (not) agree more.Confidence is really important.9The new law states that people _(not) drive after drinking alcohol.10Its quite warm here; we _(not) turn the heating on yet.11No one _ be comp

9、ared with Yao Ming in playing basketball.Oh, you are really his big fan.12The police still havent found the lost child, but theyre doing all they_.13It _ (not) be the postman at the door.Its only six oclock.14Hows your new babysitter?We _ (not) ask for a better one.All our kids love her so much.15I

10、dont really like James.Why did you invite him?Dont worry.He _ not come.He said he wasnt certain what his plans were.16If you _ smoke, please go outside.17If you _ go, at least wait until the storm is over.18Shall I inform him of the change of the schedule right now?I am afraid you _， in case he come

11、s late for the meeting.19I _ (not) worry about my weekend.I always have my plans ready beforeit comes.20Will you read me a story, Mummy?OK.You_ have one if you go to bed as soon as possible.1neednt 2.cant 3.Must 4.might 5.neednt 6.shall7can 8.couldnt 9.mustnt 10.neednt 11.can 12.can13cant 14.couldnt

12、 15.might 16.must 17.must18must 19.neednt 20.shall二、虛擬語氣考點透析1虛擬語氣在非真實條件句中的用法。時間與現在事實相反與過去事實相反與將來事實可能相反did/should do/were todo例如：(1)If she were here，everything would be all right.(But she isnt here now.)(2)If you had come five minutes earlier，you would have met the famous pop singer.(3)If it were to

13、rain tomorrow，the outing would be cancelled.(4)If you should visit our school tomorro，w you would see how beautiful it is.2wish賓語從句 (賓語從句中的動詞變化如下表)。時間動詞形式例句I wish I were ten yearsyounger.與現在事實相反的愿望did(be 改為 were)3 / 5 He wishes he had gone to theconcert last night.與過去事實相反的愿望將來難以實現的愿望had過去分詞3.在非真實條件狀

14、語從句中，如果含有 were，had，should，可將 if 省去， 將 were，had，should 放在主語前，構成倒裝。例如：4 / 5 I wish they _ always late.1had 2.would have visited 3.had been 4.might have had5did 6.could have faced 7.were 8.hadnt offered9couldnt have gone 10.werent.請根據以下要點，寫一篇有關珍惜水的短文寫作內容：1眾所周知，水在人類生活中起著非常重要的作用；2如果沒有水，我們人類就會滅絕；3如果以前我們愛惜水，現在就不會缺水了；4要是水是無窮無盡的就好了，我們就可以充分利用它；5由于水是有限的，現在是我們做點事來保護水資源的時候了。寫作要求：1只能用 5 個句子表達全部內容；2盡可能多地使用虛擬語氣。_As is known to all, water plays an important role in our life. W