1、2013屆高一英語備課組編制人：劉春美審核人：楊春樂使用日期：3月中旬4情態動詞的用法講解情態動詞有 can /could, may /might, must, have to, shall /should, will /would, dare /dared, need /n eeded, ought to等。情態動詞無人稱和數的變化；不能單獨使用，必須與其后的動詞原形構成謂語一、 can/ could1）表示能力（體力、知識、技能）。Eg. 1.Ca n you lift this heavy box?（體力）2. Mary can speak three Ianguages.（知識）3.

2、Can you skate?（技能）此時可與be able to互換，但（1）.be able to有更多的時態。（2）.當表示"經過努力才得以做成 功某事”時應用 be able to,不能用can。Eg.1. I ' ll not be able to come this after noon.2. He was able to go to the party yesterday evening in sp ite of the heavy rain.2）表示請求和允許。Eg. 1.Can I go now?Yes, you can. / No, you can'

3、 t.此時可與may互換。在疑問句中還可用could, might代替，不是過去式，只是語氣更委婉，不能用于肯定句和答語中。Could I come to see you tomorrow?Yes, you can. （ No, I' m afraid not.）3）表示客觀可能性（客觀原因形成的能力）。Eg. 1.They ' ve cha nged the timable, so we can go by bus in stead.2. This hall can hold 500 people at least.4）表示推測（驚訝、懷疑、不相信的態度），用于疑問句、否定句

4、和感嘆句中。Eg. 1.Ca n this be true?2. This can ' t be done by him.3. How can this be true?may, mightcan t 或1）表示請求和允許。might比may語氣更委婉，而不是過去式。否定回答時可用 must n't，表示"不可以，禁止”。Eg.1. -Might/ May I smoke in this room?No, you mustn' t.2. - May/Might I take this book out of the room?Yes, you can. （No

5、, you can' t / mustn' t.）用May I. ?征詢對方許可時比較正式和客氣，而用Can I. ?在口語中更常見。2）用于祈使句，表示祝愿。May you succeed!3）表示推測、可能性（不用于疑問句）。might不是過去式，它所表示的可能性比may小。Eg. 1.He may /might be very busy now.2. Your mother may /might not know the truth. must, have tomust n't （禁止，不準），1）表示必須、必要。在回答引出的問句時，如果是否定的，不能用而用 n

6、eed n't, don 'have to （不必）.Eg.Must we hand in our exercise books today?Yes, you must. No, you don ' t have to / you needn' t.2） must是說話人的主觀看法，而have to則強調客觀需要。must只有一般現在時，have to有更多的時態形式。Eg. 1.The play isn 'tinteresting，and I really must go now.2.I had to work whe n I was your age

7、.3）表示推測、可能性（只用于肯定的陳述句）Eg. 1.You re Tom's good friend, so you must know what he likes best.2. Your mother must be wait ing for you now.4）.表示“一定要；偏要”Eg. 1.Must you worry her with questi on s, just whe n she is busy cook ing dinner?2. Must you make so much no ise?即時練習：1. 那小女孩沒有出門。她現在一定在做家庭作業。The gi

8、rl is not out. She2. 路上是濕的。昨晚一定下雨了。The road is wet. It3. 我剛剛拜訪過他。他現在一定呆在家里。I have just dropped in on him. He4. 你為什么沒有接電話？我當時一定是在睡覺所以沒聽見。Why didn t you answer my phone call?Well, I , so I didn5. 那男孩想必已經完成了他的家庭作業了。her homework now.last ni ght.at home.t hear it.his homework.The boy四、 dare, n eed1) dare

9、作情態動詞用時，常用于疑問句、否定句和條件從句中，過去式為dared。Eg. 1.How dare you say I m unfair?2. He dare n'ts peak En glish before such a crowd, dare he?3. If we dared not go there that day , we couldn 'get the beautiful flowers.2) need作情態動詞用時，常用于疑問句、否定句。Eg. 1 . You needn'tcome so early.2. - Need I fin ish the w

10、ork today? Yes, you must. / No, you needn' t.3) dare和need作實義動詞用時，有人稱、時態和數的變化。在肯定句中，dare后面常接帶to的不定式。在疑問句和否定句中，dare后面可接帶to或不帶to的不定式。而need后面只能接帶to的不定式。Eg. 1. I dare to swim across this river.2. He doesn' t dare （to） answer.3. He n eeds to finish his homework today. 即時練習： How dare you say such a

11、 thing?How dare you to say such a thing?f He daren'to speak English before such a crowd, did he?I He daren'tspeak English before such a crowd, dare he?Nobody n eed to be afraid of catch ing the disease.Nobody need be afraid of catching the disease.L These dishes needed be cleaned carefully.T

12、 These dishes need to be cleaned carefully.I These dishes need cleaning carefully五、 shall, shouldShall的用法1）shall用于第一，三人稱的疑問句，征求對方的意見或提出建議。Eg. 1.What shall we do this evening?2.Shall I turn on the lights?3.Shall he wait for you outside?2）shall用于第二、三人稱，表示說話人給對方的命令、警告、允諾或威脅。Eg. 1. You shall fail if you

13、 don 'work hard.（警告）2. He shall have the book when I finish it.（允諾）3. He shall be pun ished.（威脅）3）shall表示強制，用于法令、條約、規章中，意為“必須，應該”。如：Eg. Can didates shall rema in in their seats un til all the papers have bee n collected. 即時練習：1. Will Mr Wang offer us a hand?Hebe glad to. He n ever refused our re

14、quest.A. canB. mustC. mayD. should2. “ The interestbe divided into five parts, according to the agreement made by both sides.declared the judge.A. mayB. shouldC. mustD. shall3. When can I come for the p hotos? I n eed them tomorrow after noon.D. needTheybe ready by 12 : 00.A. canB. shouldC. might4.I

15、t 'n early seve n o'clock. Jackbe here at any mome nt.D. can八、A. mustB. n eedC. shouldwill, would1）表示請求、建議等，would更委婉。Will / Would you pass me the ball, please?2）表示意志、愿望和決心。1. I will n ever do that aga in.2. They asked him if he would go abroad.3）.will表示現在的習慣，would表示過去的習慣。would表示過去習慣時比 used t

16、o正式，且沒有“現已無此習慣”的含義。Eg. 1.Whe n he was a child, he would ofte n go skii ng.2.This old man is stra nge . He will sit for hours without say ing anything.4）.表示意愿Eg.1.She won't le nd me the money .2.This window won t open.5) .will表示某些根據自然規律必定會發生的事情，物體固有的性質，傾向Oil will float on water .七、should, ought t

17、o1) should, ought to表示"應該” ，ought to表示義務或責任，比 should語氣重。Eg. 1. I should help her because she is in trouble.2. You ought to take care of the baby.2) 表示勸告、建議和命令。Eg. 1. You should / ought to go to class right away.3) should表推測，語氣比較肯定，往往具有一定的客觀根據，常譯為“理該”When can I come for the p hotos? I n eed them

18、 tomorrow after noon.They should be ready by 12:00.4) 表示“萬一”If it should rain tomorrow, don texpect me.5) 表示“竟然”It 'sstra nge that he should be late.八、情態動詞+ have done1) can / could + have done有兩層含義：1.在肯定句中表示“過去本來可以做而實際上未做某事”，是虛擬語氣2.在疑問句或否定句中表示對過去行為的懷疑或不肯定，表示推測。Eg. 1. You could have done better,

19、but you didn t try your best. (虛擬語氣)2. He can' t have been to that town.(推測)3. Can he have got the book?(推測)2) may / might + have done 1.表示對過去行為的推測。2.用于虛擬語氣中Eg.1. He may not have fini shed the work .2. If we had take n the other road, we might have arrived earlier.想必”。其疑問、3) must + have done用于肯定句中，表示對過去行為的推測。意為“一定、否定形式用can, can' t代替。Eg. 1. You must have see n the film Tita nic.2. He must have bee n to Shan ghai.，其否定式表示某4) should/ought to + have done表示“過去本應該做