專題七 情態(tài)動(dòng)詞、系動(dòng)詞

　　在英語(yǔ)中，表示主語(yǔ)動(dòng)作或狀態(tài)的詞就叫做動(dòng)詞。根據(jù)動(dòng)詞的意義及在句子中的作用，可將動(dòng)詞分為實(shí)義動(dòng)詞(v)、系動(dòng)詞(link-v)、情態(tài)動(dòng)詞(modal verb)和助動(dòng)詞(v. aux)四種類型。

　　下面我們就來(lái)看看情態(tài)動(dòng)詞和系動(dòng)詞的具體用法。

　　一、情態(tài)動(dòng)詞

　　情態(tài)動(dòng)詞本身有一定的意義，但不能獨(dú)立作謂語(yǔ)，要和動(dòng)詞原形一起構(gòu)成謂語(yǔ)，表說(shuō)話人的語(yǔ)氣和態(tài)度。它沒(méi)有人稱和數(shù)的變化。常見(jiàn)的情態(tài)動(dòng)詞有：

　　1. can表示能力，有“能”“會(huì)”的意思;表示可能性，多用在否定或疑問(wèn)句中;表示請(qǐng)求和許可。

　　如：The parrot can speak three languages. 這只鸚鵡能講三種語(yǔ)言。

　　Can I borrow the book from the library?我可以從圖書(shū)棺借這本書(shū)嗎?

　　Shanghai can be very cold in March. 上海三月份可能會(huì)很冷。

　　拓展延伸can還有過(guò)去式could 可表“能，會(huì)”，又可以和be able to替換，而be able to有 更多時(shí)態(tài)。 如：

　　He could swim when he was four. =He was able to swim when he was four. 他四歲時(shí)就會(huì)游泳。 在一般疑問(wèn)句中，can/could 常用來(lái)表示請(qǐng)求或征求對(duì)方意見(jiàn)，用could 比用can語(yǔ)氣更加委婉和客氣。類似用法的還有Will /Would you (please)…等句型。

　　如：Could you tell me how I can get to the post office? 你能告訴我怎樣到郵局嗎? Would you please turn up the radio?請(qǐng)你把收音機(jī)開(kāi)大點(diǎn)，好嗎?

　　2.may表示“許可”時(shí)，相當(dāng)于can，其否定回答用can’t/mustn’t;表推測(cè)時(shí)，常用在肯定句中，表“可能”。

　　如：-May I borrow your ruler?我可以借用您的直尺嗎?

　　-No, you can't /mustn't. 不行。

　　She may be a teacher. 她可能是一名教師。

　　拓展延伸may可表示祝愿。如： May you succeed! 祝你成功!

　　3.must表示“必須;必要”，以“must”開(kāi)頭的一般疑問(wèn)句其肯定回答用“must”，否定回答用“needn't”或“don't have to”。 must表推測(cè)時(shí)，常用在肯定句中，是“一定”的意思，其否定形式mustn ' t表“禁止”的意思。

　　如：-Must I leave now?現(xiàn)在我必須離開(kāi)嗎?

　　-No，you needn't /you don't have to. 沒(méi)有必要。

　　This book must be Lucy's . Look! Her name is on the book cover. 這本書(shū)是露西的�？�!封面上還有她的名字。

　　You mustn't draw on the wall. 你不準(zhǔn)在墻上畫(huà)畫(huà)。

　　拓展延伸must表示說(shuō)話人的主觀看法，只有一般現(xiàn)在時(shí);have to強(qiáng)調(diào)客觀要求，有時(shí)態(tài)、人稱和數(shù)的變化。如： My mother is ill. I have to look after her now. 媽媽病了，我得去照看她。

　　4.need作情態(tài)動(dòng)詞時(shí)，常用在否定和疑問(wèn)句中，表示“需要;要”的意思。

　　如：Need we finish the work now?現(xiàn)在我們需要完成這項(xiàng)工作嗎?

　　They needn ' t look after him. 他們不需要照顧他了。

　　拓展延伸need還可以用作行為動(dòng)詞，可以用于各種句型。如：

　　Does he need any help? 他需要幫助嗎?

　　The desk needs repairing. 這張桌子需要修理。

　　5.shall 用于第一人稱，表示說(shuō)話人征求對(duì)方意見(jiàn)，過(guò)去式為should;will 用手第二人稱的疑問(wèn)句中，表示說(shuō)話人向?qū)Ψ教岢稣?qǐng)求和建議，過(guò)去式為would。

　　如：Shall I go shopping with you?'我可以同你去購(gòu)物嗎?

　　I don't know what I should do next. 我不知道下一步該干什么。

　　Would you please come a little earlier?請(qǐng)你來(lái)早一點(diǎn)好嗎?

　　6.情態(tài)動(dòng)詞had better的用法

　　(1)had better 后接動(dòng)詞原形，表勸告、建議，意為“最好”�！癥ou'd better… ”含有強(qiáng)制命令的語(yǔ)氣，對(duì)長(zhǎng)輩不宜使用。

　　如：You'd better ask that policeman over there. 你最好問(wèn)一下那邊的那個(gè)警察。

　　(2)慎用had better! 注意以下四條：

　�、賖ad better表達(dá)的是說(shuō)話者強(qiáng)硬性的建議，告誡別人(包括自己)如何做。 如：Granny, the hospital is not very near. We'd better catch a bus. 奶奶，醫(yī)院不是很近。我們最好坐公共汽車。

　�、趆ad better不用于禮貌的請(qǐng)求或征詢，它隱含一種警告或威脅。 如：You ' d better finish the work today and bring it tomorrow. 你最好今天就把作業(yè)完成，明天帶來(lái)。

　�、踙ad better意思接近should，但它除了表示語(yǔ)氣強(qiáng)硬以外，還表示馬上要去做的事情，比should更緊迫。 如：You’d better see a doctor at once. 你最好馬上去看醫(yī)生。

　�、躧ad better不含比較的意思，該結(jié)構(gòu)表示“It would be good to… ”，而不是“It would be better to…”。

　　二、系動(dòng)詞

　　系動(dòng)詞有實(shí)際意義，但不能單獨(dú)做謂語(yǔ)，必須與表語(yǔ)一起構(gòu)成句子的謂語(yǔ)，說(shuō)明主語(yǔ)的性質(zhì)、狀態(tài)或身份等。 它分為完全系動(dòng)詞和不完全系動(dòng)詞。

　　1.完全系動(dòng)詞(be)可接名詞、代詞、形容詞、副詞、介詞短語(yǔ)、非謂語(yǔ)動(dòng)詞短語(yǔ)、句子做表語(yǔ)。如： I'm a student. 我是個(gè)學(xué)生。(名詞) He is fine. 他很好。(形容詞) It is me. 是我。(代詞) Are you there?你在那兒?jiǎn)?(副詞) She is at school. 她在學(xué)校讀書(shū)。(介詞短語(yǔ)) He is to come soon. 他過(guò)會(huì)兒該來(lái)了。(不定式) My job is teaching English. 我的工作是教英語(yǔ)。(動(dòng)詞的ing形式) My idea is that we will start now. 我的想法是我們現(xiàn)在就開(kāi)始。(句子)

　　2.不完全系動(dòng)詞 (get，turn，feel，smell，look，sound，taste)一般只接形容詞做表語(yǔ)。如：When spring comes, it gets warmer and warmer.

　　春天來(lái)了，天氣變得越來(lái)越暖和了。 Food may go bad soon if it is not put into a fridge.

　　食物如果不放進(jìn)冰箱里就會(huì)很快變壞。 My brother became / turned a teacher after his graduation.

　　我哥哥畢業(yè)后就當(dāng)上了老師。(注意become和turn的用法區(qū)別)

　　實(shí)戰(zhàn)演練(2×50) 計(jì)分:

　　1. --Mary, ____ you speak Chinese? -- Yes, but only a little.

　　A. will B. can C. could

　　2. --Must I do the work now? -- No, you ____. You can do it later.

　　A. can't B. mustn't C. needn’t

　　3. -- I can't stop smoking, doctor. -- For your health, I'm afraid you ____.

　　A. can B. need C. must

　　4. -- Whose book is it? -- It ____ be Bob's sister's. She is only a baby.

　　A. must B. mustn't C. can't

　　5. -- Jill looks so painful, there ____ be something wrong with her.

　　-- Oh, dear! We'd better take her to the hospital at once.

　　A. can B. should C. must

　　6. --Is Simon coming by train? -- He should, but he ____ not. He likes driving his car.

　　A. may B. need C. must

　　7. -- May I try on the jeans? -- Yes, you ___.

　　A. should B. can C. must

　　8. -- Do you know any traffic rules?

　　-- A little. When the traffic lights are red, we ____ stop and wait.

　　A. may B. can C. must

　　9. I think schools ____ allow students at least one hour a day for sports.

　　A. would B. should C. could

　　10. -- Can I swim in the lake. Dad?

　　-- No, you ____. Haven't you seen the notice “No Swimming”?

　　A. may not B. mightn't C. mustn't

　　11. -- Are you going to Beijing by air?

　　-- It's fast but a little expensive. So I am not sure. I __ take it.

　　A. will B. may C. must

　　12. -- Could I borrow your dictionary? -- Of course you ____.

　　A. can B. will C. should

　　13. --Don't forget to come to my birthday party tomorrow. --No,____.

　　A. I don't B. I won't C. I can't

　　14. -- Will you please stay here for the party?

　　-- Sorry, I ____. I'll have to go to an important meeting.

　　A. mustn't B. needn't C. can't

　　15. -- Must I tidy the room now?

　　-- No, you ____. You can do it after breakfast.

　　A. mustn’t B. need C. don't have to

　　16. -- You must come back every month. -- Yes, I ____.

　　A. will B. must C. should

　　17. -- Is this coat Jane's? -- It ____ be hers, but I'm not sure.

　　A. will B. may C. must

　　18. -- ____ we go and fly kites today? -- That's a good idea.

　　A. Should B. Must C. Shall

　　19. --ls your brother playing computer games, Ted?

　　-- He ___ do that because the computer doesn't work.

　　A. may not B. can't C. mustn't

　　20. -- I don't mind telling you what I have known.

　　-- You ___, and I am not asking you for it.

　　A. needn't B. mustn't C. may not

　　21. _____ you help me?

　　A.Will B.Shall C.Must

　　22. You ______watch TV if you’ve finished your homework.

　　A. can B. must C. need

　　23. I have seen lights in that empty house. Do you think I _____report it to the police?

　　A. should B. may C. will

　　24. -- Who is the girl standing over there?

　　-- Well, if you ______know, her name is Mary.

　　A. may B. can C. must

　　25. -- Excuse me, could you tell me where the supermarket is?

　　-- It’s two blocks straight ahead. You _____miss it.

　　A. mustn’t B. can’t C. shouldn’t

　　26. -- Mom, there goes the bell.

　　-- Oh, it _____ Annie. I invited her to come for dinner.

　　A. can’t be B. must be C. may be

　　27. I’ll let you see the patient in an hour if you _____wait here.

　　A. will B. must C. can

　　28. Whoever can answer one of my questions ______get a prize.

　　A. would B. should C. will

　　29. Tom, you ______leave all your clothes on the floor like this.

　　A. wouldn’t B. mustn’t C. needn’t

　　30. It’s 7:50. You ____hurry, or you’ll be late.

　　A. might B. will C. had better

　　31. In spring, all the flowers in the garden _______ sweet.

　　A. taste B. smell C. become

　　32. She _______ like her mother in character.

　　A. is B. seems C. looks

　　33. In late autumn leaves _______ brown.

　　A. get B. turn C. come

　　34. Look! There _______ so many people here on vacation.

　　A. have B. are C. be

　　35. His classmate_______ a singer.

　　A. were B. grew C. has become

　　36. My job is ______ you math.

　　A. to teach B. teaches C. taught

　　37. How time flies! Three years _______ really a short time.

　　A. are B. is C. was

　　38. It sounds _______ a good idea.

　　A. as B. is C. like

　　39. Her temperature _______ to be all right.

　　A. seems B. sounds C. looks

　　40. His wish to become a driver has _______ true.

　　A. turned B. come C. been

　　41. Little Jim’s speech sounds _______.

　　A. friendly B. wonderfully C. nicely

　　42. When her mother came home yesterday, it was _______ dark.

　　A. going B. running C. getting

　　43. These apples taste _______.

　　A. to be good B. good C. well

　　44. -- How about the cloth you bought yesterday?

　　-- That’s very beautiful. It _______ so soft.

　　A. felt B. feels C. is feeling

　　45. When his brother telephoned him last night, he _______ asleep.

　　A. felt B. fell C. fall

　　46. The food will _______ bad easily in such hot weather.

　　A. go B. went C. turn

　　47. It _______ that he was late for the train.

　　A. looks B. says C.seems

　　48. What does your brother look _______?

　　A. like B. as C. after

　　49. The girl’s voice is so sweet and her songs _______ very beautiful.

　　A. taste B. look C. sound

　　50. What a lovely day! I hope it _______ fine.

　　A. stayed B. will stay C. will get

　　參考答案

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