高三英語語法復(fù)習(xí)教案之情態(tài)動詞

1、高三英語語法復(fù)習(xí)教案之情態(tài)動詞一情態(tài)動詞的語法特征1. 情態(tài)動詞不能表示正在發(fā)生或已經(jīng)發(fā)生的事情，只表示期待或估計(jì)某事的發(fā)生。2. 情態(tài)動詞 除ought 和have 外，后面只能接不帶to 的不定式。3. 情態(tài)動詞沒有人稱，數(shù)的變化，即情態(tài)動詞第三人稱單數(shù)不加-s。4. 情態(tài)動詞沒有非謂語形式，即沒有不定式、分詞、等形式。情態(tài)動詞的分類和意義意義情態(tài)動詞can, may, might, could, would, will, shall, must, should, ought to, used to二情態(tài)動詞的基本用法1. can (could)1) 表示能力，could主要指過去時(shí)間。例

2、如： Two eyes can see more than one.   兩只眼比一只眼看得清。 Could the girl read before she went to school?   這女孩上學(xué)前能識字嗎？2) 表示可能（理論上或是邏輯判斷上）。例如：,>_K He cant (couldnt) have enough money for a new car.  他不可能有足夠的錢買新車。 You mustnt smoke while youre walking around in the wood. You could start a fire

3、.  在林子里走時(shí)勿吸煙，那樣可能會引起火災(zāi)。3) 表示允許。例如： Can I have a look at your new pen?   我可以看一看你的新鋼筆嗎？ He asked whether he could take the book out of the readingroom.  他問他可不可以把書帶出閱覽室。4) 表驚異、懷疑、不相信等態(tài)度。主要用于否定句、疑問句或感嘆句中。例如： Where can (could) they have gone to?   他們會去哪兒了呢？ How can you be so careless?

4、   你怎么這么粗心？5) 比較委婉客氣地提出問題或陳述看法。例如： Can (Could) you lend me a hand?   幫我一把好嗎？. Im afraid we couldnt give you an answer today.  恐怕我們今天不能給你答復(fù)。2may (might) 1) 表允許，might可以指過去時(shí)間，也可指現(xiàn)在時(shí)間，語氣更委婉。例如： You may take whatever you like.你喜歡什么就拿什么。 May (Might) I ask for a photo of your baby? 我可以要一張你寶寶

5、的照片嗎？在回答以may引起的問句時(shí)，多避免用這個(gè)詞，而用其它方式，如Yes, please. / Certainly. / Please dont. / Youd better not. / No, you mustnt.等，以免顯得太嚴(yán)峻或不客氣。2) 表可能（事實(shí)上）。可以指過去時(shí)間，也可以指現(xiàn)在時(shí)間，但語氣更加不肯定。例如： He may be at home.   他可能在家。 She may not know about it.   她可能不知道這件事。3must1) 表示義務(wù)。意為“必須”（主觀意志）。例如： We must do everything ste

6、p by step.   我們一切都必須循序漸進(jìn)地做。 -Must we hand in our exercise books now?我們現(xiàn)在就要交練習(xí)本嗎？-No, you neednt. / No, you dont have to.   不必。4) 表示揣測。意為“想必、準(zhǔn)是、一定”等，只用于肯定句。例如： He must be ill. He looks so pale.   他準(zhǔn)是病了。他的臉色蒼白。 Shes wearing a diamond necklace. She must have a lot of money. 她戴著鉆石項(xiàng)鏈，一定很有錢

7、。:4shall 1) 表征詢意見，用于第一、第三人稱疑問句。例如： Shall I get you some tea?   我給你點(diǎn)茶好嗎？ Shall the boy wait outside?  讓那男孩在外面等嗎？2) 表說話人的意愿，有“命令、允諾、警告、決心”等意思，用于第二、第三人稱陳述句。例如： You shall do as I say. 按我說的做。（命令） You shall have my answer tomorrow. 你明天可以得到我的答復(fù)。（允諾） He shall be sorry for it one day, I tell you. 有

8、一天他會后悔的，我告訴你。（警告） Nothing shall stop us from carrying out the plan. 什么也不能阻止我們執(zhí)行這項(xiàng)計(jì)劃。（決心）5will 1) 表意愿，用于各種人稱陳述句。例如： I will do anything for you.   我愿為你做任何事。 None is so blind as those who wont see.   不愿看的人眼最瞎。 If you will read the book, Ill lend it to you.  如果你愿意讀這本書，我會把它借給你。2) 表請求，用于疑問句

9、。例如： Will you close the window?   請你把窗戶關(guān)上好嗎？ Wont you drink some more coffee?   再來一點(diǎn)咖啡好嗎？3) 表示某種傾向或習(xí)慣性動作。例如： Fish will die out of water.   魚離開水就不能活。 The door wont open.  這門打不開。6. should1) 表義務(wù)。意為“應(yīng)該”（某件事宜于做），用于各種人稱。例如： You should be polite to your teachers.   你對老師應(yīng)該有禮貌。 You s

10、houldnt waste any time.   你不應(yīng)該浪費(fèi)時(shí)間。2) 表推測，意為“想必一定、照說應(yīng)該、估計(jì)”等。例如： The film should be very good as it is starring first-class actors.  這部新電影是一流演員主演的，估計(jì)拍得很好。 They should be home by now.   照說他們現(xiàn)在應(yīng)當(dāng)已經(jīng)到家了。3)（表示不確定）萬一。例如： If I should see him, I'll tell him. 萬一我見到他，我就告訴他。 If it should rain

11、 tomorrow, the sports meeting would be postponed. 萬一明天下雨,比賽就延期舉行。"7.  would1) 表意愿。例如：: They would not let him in because he was poorly dressed. 他們不讓他進(jìn)去因?yàn)樗轮婆f。 I said I would do anything for you.   我說過我愿意為你做任何事。2) 表委婉地提出請求、建議或看法。例如： Would you mind cleaning the window?   請把窗戶擦一下好嗎

12、？ They wouldnt have anything against it.   他們不會有什么反對意見。3) 表過去反復(fù)發(fā)生的動作或過去的一種傾向。例如：:Every time she was in trouble, she would go to him for help.   她每遇到麻煩都會向她求助。他告訴我盒子打不開了。8.ought to 1) 表義務(wù)，意為“應(yīng)該”（因責(zé)任、義務(wù)等該做），口氣比should稍重。例如： You are his father. You ought to take care of him.你是他父親，應(yīng)當(dāng)管他。 You ough

13、tnt to smoke so much.   你不應(yīng)該抽這么多煙。2) 表推測，暗含很大的可能，語氣較弱。例如： Han Mei ought to know his telephone number. 韓梅該知道他的電話號碼。 Theres a fine sunset; it ought to be a fine day tomorrow.  今天有晚霞，明天應(yīng)該是個(gè)好天。9. used to表示過去的習(xí)慣動作或狀態(tài)，現(xiàn)在不復(fù)發(fā)生或存在。疑問式和否定式有兩種。例如：i There used to be a building at the street corner, bu

14、t it has been pulled down.   街道拐角處過去有座樓房，現(xiàn)在拆了。 I usednt (didnt use) to smoke.   我過去不抽煙。j F Used you (Did you use) to go to school on foot? 你過去常步行去學(xué)校嗎？10.特殊情態(tài)動詞need和dare的用法：need和dare既可用作情態(tài)動詞，也可用作實(shí)義動詞。用作情態(tài)動詞時(shí)，主要用于否定句和疑問句。用作實(shí)義動詞時(shí)，可用于各種句式。1) 用作情態(tài)動詞。例如：| You neednt telephone him now.   你現(xiàn)在

15、不必打電話給他。 I dont think you need worry.   我想你不必發(fā)愁。 She dare not go out alone at night.   她晚上不敢一個(gè)人出去。 How dare you say Im unfair?   你竟敢說我不公平？_2) 用作實(shí)義動詞。例如： You dont need to do it yourself.   你不必親自做這件事。 We need to tell them the news.   我們需要把這消息告訴他們。 The table needs painting (to

16、be painted.).   桌子需要油漆一下。 We should dare to give our own opinion.   我們要敢于提出自己的觀點(diǎn)。 He did not dare (to) look up.   他不敢抬頭看。 I dare say hell come again.   我想他會再來的?！咀⒁狻浚↖ dare say為固定習(xí)語） 難點(diǎn)突破1. 情態(tài)動詞后跟完成式和進(jìn)行式的用法1) 情態(tài)動詞+動詞完成式情態(tài)動詞+動詞完成式即“情態(tài)動詞+ have + done分詞”，表示對過去行為或動作進(jìn)行推測、評論或判斷。must hav

17、e done 表示對過去某事的肯定猜測。其否定或疑問形式都用can(could) 來表示。  例如：   Since the road is wet, it must have rained last night. He cant have missed the way. I drew him a map. The dictionary has disappeared. Who could have taken it?當(dāng)然對現(xiàn)在發(fā)生或?qū)戆l(fā)生的事情,要用must do 表示猜測, 否定為cant do。例如： He must understand that we mean

18、business. You must be hungry after a long walk.may / might have done表示推測過去某事“也許”發(fā)生了.may 比 might 表示的可能性在說話人看來稍大些。例如： I cant find my keys. I may / might have left them at the school yesterday.could have done 在肯定句型中, 往往用作委婉的批評. 本應(yīng)該做什么,而沒做; 有時(shí)也用作猜測。例如： You could have told us earlier. Tom could have take

19、n the dictionary.ought to / should have done和 ought not to / shouldnt have done用于對已發(fā)生的情況表示“責(zé)備”、“不滿”，分別表示“本應(yīng)該”和“本不應(yīng)該”。例如： With all the work finished, I should have gone to the party last night. You ought not to have made fun of him. He is not the one you laugh at but learn from.neednt have done 表示過去做

20、了某事，但沒有做的必要， 意為“本沒必要”。例如： You neednt have waken me up; I dont have to go to work today.【注意】表示推測過去某動作發(fā)生的可能性時(shí)，就表示的可能性程度而言，must最大，could其次，may更次之，might最小。例如：    -I wonder how Tom knew about your past.  -He must / could / may / might have heard of it from Mary.2) 情態(tài)動詞+動詞進(jìn)行式情態(tài)動詞+行為動詞進(jìn)行式（即情態(tài)

21、動詞+ be + doing形式），表示推測或評論某動作現(xiàn)在是否正在進(jìn)行。例如： He must be playing basketball in the room. She may be staying at home.3) 情態(tài)動詞+動詞完成進(jìn)行式情態(tài)動詞+行為動詞完成進(jìn)行式（即情態(tài)動詞+ have been + v-ing形式），表示推測或評論過去某動作是否正在進(jìn)行或一直在進(jìn)行。例如： They should have been meeting to discuss the problem. He may / might have been buying stamps in the po

22、st office when you saw him.| 考題剖析例題1. I didn't hear the phone. I _ asleep. (NMET 89)A. must be     B. must have been       C. should be     D. should have been;答案 B  從原題中的I didn't hear the phone這一信息可以判斷出，用must have done表示對過去事實(shí)的準(zhǔn)確的肯定猜測。例題2. Tom ought no

23、t to             me your secret ,but he meant no harm. (NMET93)         A. have told     B. tell      C. be telling      D. having told答案 A   該句意思是：“湯姆本來不該告訴我你的秘密，但他沒有傷害你的意思。”例題3. I was really anxious abou

24、t you. you    home without a word. (NMET2001)A. mustn't leave             B. shouldn't have leftC. couldn't have left        D. needn't leave.答案 B  shouldn't have done為不該做了某事。例題4. -Could I borrow your umbrella, plea

25、se?       -Im afraid you _.      A. could         B. can      C. couldnt        D. cant答案 D  此題極易錯(cuò)選C。其實(shí)could在問句中表示請求，為了語氣的委婉和客氣才用過去式，而答句必須按照實(shí)際情況回答，故選cant，以求和Im afraid（在此表示婉拒）一致。例題5. -Don't forget to co

26、me to my birthday party tomorrow.      -_.A. I don't B.I won't C. I can'tD. I haven't 答案 B will既可當(dāng)作情態(tài)動詞，表請求、建議、也可作為實(shí)義動詞表"意愿、意志、決心"，本題表示決心，故選B。例題6. -Shall we go skating or stay at home?-Which _ do?A. do you ratherB. would you rather C. will you rather D. shoul

27、d you rather答案 B   本題考查情態(tài)動詞would rather的用法，would rather +do sth 意為“寧愿”，本題為疑問句，would 提前，所以選B。思考：幾組情態(tài)動詞的辨異 1. can 和be able to情態(tài)動詞can只有兩種時(shí)態(tài)形式，現(xiàn)在式can和過去式could，而be able to有多種時(shí)態(tài)形式。例如： Mary can play the piano. She has been able to play it since she was 5.   瑪麗會彈鋼琴。她五歲起就會彈了。用在過去時(shí)中，could經(jīng)常表示能夠做某事，事

28、實(shí)上不一定去做，而was / were able to則表示“過去做成了某事”。在否定句中兩者可通用。例如： He could swim across the English Channel. But he didnt feel like it that day.  他能游過英吉利海峽，但那天他不想游。 Yesterday I was able to get home before the heavy rain.   昨天我在下大雨前趕到了家里。2. must和 have to must 和 have to 都可以表示“必須”，但有幾點(diǎn)區(qū)別：must 強(qiáng)調(diào)“內(nèi)在的職責(zé)”、“

29、義務(wù)”，而have to 強(qiáng)調(diào)“外界壓力”、“不得已而為之”。have to可用于多種時(shí)態(tài)，而must一般用于現(xiàn)在時(shí)，其過去時(shí)與將來時(shí)分別由had to與shall / will have to代替。在回答must引起的問題時(shí)，如果是否定的答復(fù)，不能用mustnt，而要用neednt或dont have to，因?yàn)閙ustnt是“一定不要”、“一定不能”的意思。例如： You must come to the classroom before eight.  八點(diǎn)前你必須來教室。 It is raining hard outside, but I have to leave now.

30、  雖然外面下著大雨，可我還是得走了。 -Must we do it now?    我們必須現(xiàn)在做嗎？-No, you neednt.   不，不必。3. would和used toused to表示過去與現(xiàn)在或過去某時(shí)與后來的情況有不同，而would只表過去的情況。例如： People used to think that the earth was flat.過去人們認(rèn)為地球是平的。（現(xiàn)在人們不這么認(rèn)為。） She would go out for a walk in the morning when she was in the country.

31、在鄉(xiāng)下時(shí)，她總是在早晨去散會兒步。（可能現(xiàn)在仍有散步的習(xí)慣。）used to可表示過去的習(xí)慣動作和經(jīng)常的情況，而would只表示過去的習(xí)慣動作。例如： He used to would smoke while writing.   過去他寫東西時(shí)常抽煙。 She used to be fat.   她過去很胖。4. can 和 may考試中主要測試can，may或could，might表示可能性的區(qū)別及對may構(gòu)成的疑問句的回答can, could, may, might都可以表示可能性.can, could表示潛在的可能性或理論上或邏輯判斷上存在的可能性；而may, mi

32、ght則表示事實(shí)上的可能性。此外，can還具有“有能力”的意思，而may與might則不具此意。例如： According to the weather forecast, it may rain tomorrow.   據(jù)氣象預(yù)報(bào)，明天可能下雨。 Any man with a little sense can see that he is wrong.   任何一位有頭腦的人都能看出他錯(cuò)了。May I / we ？這一類疑問句的肯定回答為Yes, please.或Certainly；否定回答為Please dont.或No, you mustnt. 例如：  &

33、#160; -May we leave now?    我們可以走了嗎？-No, you mustnt. You havent finished your home work yet.   不行，你們還沒完成工作呢。5. used to +do, be used to +doing和be used to +doused to +v意為“過去常?！保斑^去一直”；be used to +v-ing /  n（名詞）意為“習(xí)慣于”；be used to +v意為“被用來（做某事）”。used to只表示過去，而be used to +v-ing / n可表示

34、現(xiàn)在、過去或?qū)?。例如?He used to smoke. Now he doesnt.   他過去吸煙，現(xiàn)在不吸了。 Hes quite used to hard work / working hard.   他習(xí)慣于埋頭苦干。 The knife is used to cut bread.   這把刀是用來切面包的。6. 用作情態(tài)動詞的其他短語would rather, would sooner, would (just) as soon, had rather, had better, had sooner, can not but, may  (just) as well等可用作情態(tài)動詞。例如： The soldier would sooner die than surrender.   那士兵寧死不屈。 Id rather walk than take a bus.    我寧愿步行也不愿乘車。 If you dont like to swim, you may just as well stay at home.   如果你不想游泳，你也可以呆在家里?！咀⒁狻窟@些短語后一般直接跟動詞原形.w