1、情態動詞用法情態動詞的語法特征2) 情態動詞不能單獨做謂語, 后面只能接動詞原形，ought to和have to除外，。 3) 情態動詞沒有人稱, 數的變化, 但有些情態動詞, 如can、will、have to、may等有過去式。1）情態動詞表說話人的某種感情或語氣，對某一動作或狀態的某種態度。1) Some of us can use the computer now, but we couldnt last year.2) Can she be in the computer center?3) I though what he said could not be true.4) Ca

2、n/Could I use your dictionary?5) Could you lend me a hand?1.表能力,意為“能，能夠”，can指現在，could指過去。3. 表示“請求” “允許”(表請求時，口語中常用 could 代替 can 使語氣更委婉，回答時用can)2. 表示推測，意為“可能”“或許”，用于疑問句或否定句，cant和couldnt意為“不可能”。1. can 與could4. can 用于疑問句或否定句中時，表驚異、不相信等，意思是“可能、能夠”。6) How can you believe such a liar like him?5. cant/ cou

3、ldnt have done 表示對過去情況的否定推測,意為“過去不可能做過某事”7) Susan cant have written a report like this.8) She cant have gone to school, it is Sunday .6. can/could have done表對過去的推測，意為“過去可能做了某事”。 could have done還可以表示對過去能做而未做的事情感到惋惜，意為“本能夠做某事可事實上未做”9）Its a pity. Your class could have got the first prize.10）Where can M

4、ary have gone?can表示“能夠”時與短語be able to同義，但can只用于一般現在時或過去時，而后者可用于各種時態。另外，can表示個人有某種能力，而be able to表示某人通過努力、克服困難做成某事，相當于succeed in doing sth.；can/be able to Michael _ be a policeman, for hes much too short. A. neednt B. cant C. should D. may2. Mr. Bush is on time for everything. How _ it be that he was

5、late for the opening ceremony? A. can B. should C. may D. must3. - I stayed at a hotel while in New York. - Oh, did you? You _ with Barbara. A. could have stayed B. could stay C. would stay D. must have stayedMy sister met him at the Grand Theater yesterday afternoon, so he _ your lecture. A. couldn

6、t have attended B. neednt have attended C. mustnt have attended D. shouldnt have attendedBAAA5. Theres someone outside. Who _it be? A. can B. need C. may D. must6. -Is Jack on duty today? -It _ be him. Its his turn tomorrow. A. mustnt B. wont C. cant D. neednt7. It is usually warm in my hometown, bu

7、t it _be rather cold sometimes. A. can B. need C. dare D. must8. The fire spread through the hotel very quickly, but everyone _ get away. A. were able to B. would C. was able to D. couldACAC2. may 與might1. 表示“許可”或“請求”，有“可以”的意思，口語中 常用 might 代 may ,表示委婉語氣。 否定回答時用“must not”表“禁止，阻止”， 不用 “may not”. “may

8、not” 表示“可能不” 。Eg: 1)- May I watch TV after supper? - Yes, you may. / No, you mustnt. 2) Today is Sunday. She may not in her office now.2. 表示可能性。 意為“或許，可能” might 比 may 可能性小。Eg: 1) The girl might be sleeping this time of day. 2) They may be in the library now.4. may/ might as well + 動詞原形 “還是的好” “不妨干某事

9、” Eg: You may as well go and have a look.3.may/might have done 表示對過去發生過的事情的推測，意為“可能已經做過某事”Eg: I cant find my sunglasses. I may/might have left them in your office.1.Sorry Im late. I _ have turned off the alarm clock and gone back to sleep again. A. might B. shouldC. can D. will2.Peter _ come with us

10、 tonight, but he isnt very sure yet. A. must B. may C. can D. willAB3. will 與would 1. 用于第二人稱的疑問句中，表“請求、建議”等，用 would 比用will 委婉，客氣些Eg: 1)Will you lend me your book? 2) Would you like a cup of tea?2. 用于表示意志或意愿，意為“會，愿意” 。will 指現在，而 would 指 過去。用于否定句中，表示“不會、不肯、不樂意”。Eg: 1) I wont do that again. 2) They sai

11、d that they would help us. 3) No matter what I said, he wont listen to me.3.表示習慣性動作。 譯作 “總是、慣于”， will 指現在常常，would 指過去常常。Eg: 1)This man is strange. He will sit for hours without saying anything. 2) Mary will keep asking some silly questions. 3) Every evening, she would sit by window, deep in thought.

12、 4) We would sit around Grandpa after supper, listening to his stories.If you _ wait here for another 5 minutes, our manager will come back. A. should B. will C. need D. must2. When he was there, he_ go to that coffee shop at the corner after work every day. A. would B. should C. had better D. might

13、 BA4. should與ought to1. ought to比should語氣更重。兩者都用于表勸告、建議。 意為”應該、應當”。但在疑問句中常用should。ought to的否定式為oughtnt to或ought not to。Eg: I should help her because she is in trouble. You ought to take care of the baby. Should I open the window? What should we do next? 2. 兩者都可表示推測，表示很大的可能性。意為 “可能、按理該”Eg: 1) Its 7 o

14、clock, he should be at home. 2) They should have arrived by now.3. ought to/should have done 本應該干某事可事實未干 oughtnt to/shouldnt have done本不該干某事可事實 卻干了Eg: You should have invited me to the party yesterday. You are right. I Should have thought of that. You shouldnt have eaten all the cakes in one day. 4.

15、 Should可以用來表示說話人的驚奇等情感，意為“竟然，居然”Eg: 1) Its surprising that Mary should love such a person. 2) Its unbelievable that the boy should sing such a beautiful song.1.You cant imagine that a well-behaved gentleman _ be so rude to a lady. A. can B. should C. may D. must2. - When can I come for the photos? I

16、 need them tomorrow afternoon. - They _ be ready by 12:00 A. can B. should C. might D. need3. We _ last night, but we went to the concert instead. A. must have studied B. might study C. ought to have studied D. would studyBBc5. shall1. Shall用于第一、三人稱的疑問句中，表示說話人征求對方的意見或請求。 Eg: 1) Shall we begin our di

17、scussion? 2) Shall I change the clothes for the child? 3) Shall Tom go there with me tomorrow? 4) Henry is waiting outside. Shall he come in? 2. Shall用于二、三人稱的陳述句，表示說話人 的允諾、警告、命令、威脅等語氣。Eg: 1)You shall get an answer from me tomorrow. 2) He shall be punished. 3) You shall go with me. 4) Tell Jerry that

18、 he shall get a gift if he behaves well.Chairman Zhang, many people want to see you. _they wait here or outside? A. shall B. can C. should D. may2. You _use my bike if you can return it to me before Ileave here. A. should B. shall C. need D. must3. You _be punished if you break the rule. A. shall B.

19、 should C. need D. mustABAmust/haveto/need1.must用于一般問句中,肯定回答用must,否定回答用neednt或dont have to，意為“不必”。mustnt表示“禁止，不允許” MustIfinishallhomeworkatatime? Yes, you must. No,youneednt/dont have to.I dont like this TV set. We must buy a new one. Mother was out, so I had to look after the shop.2.表示“必須”這個意思時，mus

20、t和haveto稍有區別。must著重說明主觀看法，haveto強調客觀需要。另外，haveto能用于更多時態。 Youmustbethenewteacher. Hemustbejoking. Thereisnobodyhere.Theymusthaveall gonehome. 3.must表示對某人某事的肯定猜測, 作“準是”, “一定” , 用于肯定句中。對過去發生的事情作肯定判斷用must have done，意為過去一定已經做過某事。Why must you always interrupt me?If you must smoke, do it outside, pleaseWhy

21、 must it rain on Sunday?4. must表示與說話人愿望相反，翻譯成“偏要，硬要，非要”5.注意對need問句的回答: -Need I finish the work today? -Yes, _. No, _. No, _.you mustyou needntyou dont have to-Must we do it now? -No, you _. neednt(dont have to)【考例】The boss has given everyone a special holiday, so we _ go to work tomorrow. (上海 2007春)

22、A. cant B. mustntC. neednt D. shouldnt【點撥】考查情態動詞。根據題意, 可知這里表示“沒有必要”, 故只能選C項?！究祭縒hat do you think we can do for our aged parents?You _ do anything except to be with them and be yourself. A. dont have to B. oughtnt toC. mustnt D. cant 【點撥】根據題意“除了和他們呆在一起做你自己外, 沒有必要做任何事情?！笨芍@里選擇dont have to表示“不必”。故選A項。

23、【考例】 -Jane has just come back from China and she looks happy.- She _ her trip very much.must enjoy B. must have enjoyedC. may enjoy D should have enjoyed【考例】 You _ return the book now, you can keep it until next week if you like.cant B. mustntC. neednt D. may not【考例】Where is Dad, Mary? He _ the flow

24、ers in the garden.must water B. must be wateringC. Must have watered D. watered【考例】-Whats the matter with the man hanging his head there? -Well. If you _know, he was caught stealing my bike.must B. may C. can D. shall情態動詞表推測用法小結情態動詞對現在或將來情況的推測對現在或將來正在進行的推測對過去情況的推測肯定推測 mustmust+vmust+be doingmust+hav

25、e done可能推測may/mightmay/might+vmay/might+be doingmay/might+have done否定推測cant/couldntcant/couldnt+vcant/couldnt+be doingcant/couldnt+have done疑問推測can/couldcan/could+vcan/could+be doingcan/could+have done 情態動詞 + have done這是歷年高考熱點之一，可表示“推測、責備、懷疑”等多種意義。一、表示對過去事情的推測或估計1. must have done “過去肯定已經做了某事” eg: The ground is rather wet, so it must have rained last night.2. may/might have done “可能/大概已經做了某事” eg: Tom may have gone to shangha