必修三英語unit1情態(tài)動(dòng)詞的用法

1、Modal Modal VerbVerb情態(tài)動(dòng)詞情態(tài)動(dòng)詞情態(tài)動(dòng)詞表示說話人的情態(tài)動(dòng)詞表示說話人的語氣語氣和和情情態(tài)態(tài)的動(dòng)詞。的動(dòng)詞。語氣語氣：能力、義務(wù)、建議、允諾、：能力、義務(wù)、建議、允諾、許可、推測(cè)。許可、推測(cè)。情態(tài)情態(tài)：情感和態(tài)度。：情感和態(tài)度。觀察下列各句，注意謂語動(dòng)詞形式。1.He can finish the paper in an hour.2.Would you please pass me the dictionary?3.She may be very busy now.4.I will never forget the days we spent together.5.W

2、e should help each other.情態(tài)動(dòng)詞的語法特征情態(tài)動(dòng)詞的語法特征1.1.不能單獨(dú)做謂語，即是情態(tài)動(dòng)詞不能單獨(dú)做謂語，即是情態(tài)動(dòng)詞+ +動(dòng)詞原形。動(dòng)詞原形。 例如：例如：I I can swimcan swim. .（謂語）（謂語） ( (除除ought to ought to “應(yīng)該應(yīng)該”和和have tohave to“不得不不得不”外外) ) 2.2.情態(tài)動(dòng)詞沒有人稱，數(shù)的變化。情態(tài)動(dòng)詞沒有人稱，數(shù)的變化。3.3.有些情態(tài)動(dòng)詞有一般式和過去式，過去式比一有些情態(tài)動(dòng)詞有一般式和過去式，過去式比一般式更委婉。般式更委婉。 如如can-could , will-would,

3、 may-might,can-could , will-would, may-might, shall-should shall-should建議建議, 請(qǐng)求請(qǐng)求, 允許允許, 能力能力Jim isnt good at maths, but he can speak English well.May I have a look at your Iphone?Would you like to join my family for dinner?When going by plane, you should arrive on time.When you eat fish, you must b

4、e very careful with the bones. 能力能力請(qǐng)求請(qǐng)求/允許允許請(qǐng)求請(qǐng)求建議建議建議建議情態(tài)動(dòng)詞語法目錄 一、一、can / could 二、二、may /might 三、三、will /would 四、四、shall / should 五、五、must I can/ am able to swim.I could/ was able to climb a tree when I was a child.I will be able to swim next week.The fire spread through the hotel very quickly but

5、everyone was able to get out 1. can 表示現(xiàn)在的能力表示現(xiàn)在的能力2. could表示過去的能力表示過去的能力3. be able to 表能力，可用于多種時(shí)態(tài)表能力，可用于多種時(shí)態(tài)4. be able to 強(qiáng)強(qiáng)調(diào)某人通過努力克服調(diào)某人通過努力克服困難成困難成功地做了某事功地做了某事一、情態(tài)動(dòng)詞表能力一、情態(tài)動(dòng)詞表能力2. 表表“許可許可”，譯為，譯為“可以可以”，could比比can語氣較委婉。用語氣較委婉。用can 或或cannot / cant 回答回答 -Can /Could I borrow your bike for a moment?-Yes,

6、 you can. / No, you cant.3. 表表“可能性可能性”，譯為，譯為“可能可能”；Can this news be true?Where can they be?否定句中，翻譯為否定句中，翻譯為“不可能不可能”She cant have left school, for her bike is still here. 情態(tài)動(dòng)詞情態(tài)動(dòng)詞 含義含義否定式否定式 注意點(diǎn)注意點(diǎn)can / could表能力表能力“能，會(huì)能，會(huì)”cant“不會(huì)，不能不會(huì)，不能”區(qū)別區(qū)別 be able to表許可表許可“可以可以”cant “不可以，不許不可以，不許”代替代替may表推測(cè)表推測(cè)“可能可

7、能”cant “不可能不可能”主要用于主要用于否定、否定、疑問句疑問句中中1表示某人通過努力克服困難做成某事表示某人通過努力克服困難做成某事,要用要用was / were able to.2 could, might, would 表委婉語氣用于疑問句表委婉語氣用于疑問句, 答語仍須用答語仍須用 can, may, will.3 can 用于肯定句中用于肯定句中, 可表示可表示”有時(shí)可能有時(shí)可能”情態(tài)動(dòng)詞情態(tài)動(dòng)詞 含義含義否定式否定式 注意點(diǎn)注意點(diǎn)can / could表能力表能力“能，會(huì)能，會(huì)”cant/couldnt“不會(huì)，不能不會(huì)，不能”區(qū)別區(qū)別 be able to表許可表許可“可以可

8、以”cant /couldnt“不可以，不許不可以，不許”表推測(cè)表推測(cè)“可能可能”cant /couldnt“不可能不可能”主要用于主要用于否定、疑否定、疑問句問句中中補(bǔ)充：金版補(bǔ)充：金版12頁右邊第頁右邊第4點(diǎn)點(diǎn)May I eat KFC if I finish my homework?may/might:1. 表示許可。表示請(qǐng)求、允許時(shí)，表示許可。表示請(qǐng)求、允許時(shí)，might比比may的語氣更委婉一些。的語氣更委婉一些。 Might/May I use your computer? Yes, you can. /No, you cant/you may not / you mustnt.

9、may/might:2.用于祈使句中表示祝愿。用于祈使句中表示祝愿。3.表示推測(cè)、可能（只用于肯定句，表示推測(cè)、可能（只用于肯定句，疑問句則要用疑問句則要用can或或could）。）。 祝你成功！祝你成功！ May you succeed. He may be very busy now. May you be happy all your life. 情態(tài)動(dòng)詞情態(tài)動(dòng)詞 含義含義否定式否定式may /might表許可表許可“可以可以”mustnt 不許，嚴(yán)禁不許，嚴(yán)禁may not 最好不要最好不要表推測(cè)表推測(cè)“可能可能”may not 可能不可能不 will 和和 wouldWill you

10、 give him a message when you see him. 用于第二人稱，表用于第二人稱，表“詢問意愿，提出詢問意愿，提出請(qǐng)求請(qǐng)求”would you(用于現(xiàn)在時(shí)用于現(xiàn)在時(shí))語氣更為婉轉(zhuǎn)語氣更為婉轉(zhuǎn)2. We will help him if he asks us to. 表表“意志，意愿意志，意愿”，譯為，譯為“會(huì)會(huì)”過去時(shí)：過去時(shí)：would I promised that I would do my best. 3. He will always take a walk after supper. 習(xí)慣上會(huì)發(fā)生的事情習(xí)慣上會(huì)發(fā)生的事情During the vacation

11、 he would often visit me.(過去式過去式)4. 某種特定情況下真實(shí)或可能的事情某種特定情況下真實(shí)或可能的事情 At that time, people would starve if food was difficult to find.情態(tài)動(dòng)詞情態(tài)動(dòng)詞 用用 法法will1.表請(qǐng)求表請(qǐng)求(第二人稱第二人稱)2.表意志表意志,意愿意愿3.表某種表某種傾向或傾向或習(xí)慣習(xí)慣4.某種特定某種特定情況下真實(shí)情況下真實(shí)或可能的事或可能的事情情would更客氣的更客氣的請(qǐng)求請(qǐng)求過去的意志過去的意志,意愿意愿過去的過去的傾向或傾向或習(xí)慣習(xí)慣過去某特定過去某特定情況會(huì)發(fā)生情況會(huì)發(fā)生的事

12、情的事情shall:1.Shall用于第一、第三人稱疑問用于第一、第三人稱疑問句中，表示說話人征求對(duì)方的意句中，表示說話人征求對(duì)方的意見、向?qū)Ψ秸?qǐng)示或提供幫助見、向?qū)Ψ秸?qǐng)示或提供幫助 。1.Shall we begin our lesson? 2.When shall he be allowed to leave hospital? 3.Shall I carry this bag for you?shall:2.Shall用于第二、第三人稱，表用于第二、第三人稱，表示說話人給對(duì)方命令、警告、允示說話人給對(duì)方命令、警告、允諾或威脅。諾或威脅。 You shall fail if you don

13、t work harder. He shall be punished according to the rule. He shall have the book when I finish it. 警告警告威脅威脅允諾允諾 should 1. Young people should respect old people. should 表表“義務(wù)，建議義務(wù)，建議”。 2. Its five oclock. John should be at home now. 表推測(cè)，按道理應(yīng)當(dāng)。譯為表推測(cè)，按道理應(yīng)當(dāng)。譯為“理應(yīng)，估計(jì)理應(yīng)，估計(jì)We have prepared a fridge of go

14、od and drinks. That should be enough for the party.3.表示表示 “竟然竟然” Its a pity that he should be so rude to a lady. 情態(tài)動(dòng)詞情態(tài)動(dòng)詞 用用 法法 shall征求對(duì)方意見征求對(duì)方意見(第一第一, 三人稱三人稱)表示命令表示命令,警告警告, 威脅威脅或允諾或允諾 should / ought to表示勸告表示勸告,建議建議,命令或責(zé)任命令或責(zé)任“應(yīng)該應(yīng)該, 必須必須”表示推測(cè)表示推測(cè), “理應(yīng)理應(yīng), 估估計(jì)計(jì), 大概大概”should 還還可表示可表示“竟然竟然”must 表“必須” do

15、nt have to dont need to neednt Must we hand in our exercisebooks today? Yes,you must/ No,you dont have to 2.1. 不必須不必須mustnt 禁止 表表“推測(cè)推測(cè)”時(shí)：時(shí)： 肯肯: must be +表語表語 (一定一定） 否否: cant (不可能不可能) e.g. That cant be Mary. She is in New York.3. have to “不得不不得不”，表客觀需要，表客觀需要情態(tài)動(dòng)詞情態(tài)動(dòng)詞 含義含義否定式否定式注意點(diǎn)注意點(diǎn)must表必要表必要“必須必須”ne

16、ednt“不必不必”( 區(qū)別區(qū)別 have to)有時(shí)表有時(shí)表“偏要偏要”表推測(cè)表推測(cè)“一定一定” cant“不可能不可能”只能只能用于用于肯定肯定句，句，不能不能用于用于否定、疑問句否定、疑問句You _ buy a gift, but you can if you want to.must B. mustnt C. have to D. dont have to2. When I was young, I was told that I _ play with fire. A. wouldnt B. neednt C. mustnt D. darent3. - May I smoke he

17、re ? - If you _, choose a seat in the smoking area. A. should B. could C. may D. must情態(tài)動(dòng)詞表推測(cè)情態(tài)動(dòng)詞表推測(cè)可能性的強(qiáng)弱層次must should/ought to can/could may/might1. That _ be Anns husband, for I am sure that he doesnt wear glasses.A. cant B. may not C. mustnt D. neednt 2. - Good morning. I got an appointment with

18、Miss Smith yesterday. - Ah, you _ be Mr. Peter.A. might B. must C. would D. can3. What do you mean, there are only ten tickets? There _ be twelve.A. should B. would C. will D. shall4. It is usually warm in my hometown in March, but it _ be rather cold sometimes. A. must B. can C. should D. would5. A

19、lthough this _ sound like a simple task, great care is needed. A. must B. may C. shall D. should32閱讀下列學(xué)生書面表達(dá)常見錯(cuò)誤句子并改正：1.Thanks to your help,I can back to school again.2.You will happy when you get a gift.3.You can be taken Bus No.3 to the theatre.4.We should to help each other.5.You can coming a lit

20、tle earlier.6.You must be return the book before the Summer vacation.7.I will waiting for you at the entrance .8.You should bought a small gift when you visit a friend of yours.go backbetakecomewaitbuy33假如你是李華，你的美國朋友Jack四月份即將來中國旅游，寫信向你了解你所在城市的天氣、食及交通等方面的情況。請(qǐng)你根據(jù)提示用用英文給Jack 寫一封回信。1.四月天氣暖和，四月底有點(diǎn)熱，建議他帶薄

21、外套、T恤和短褲。2.飲食：有很多中國傳統(tǒng)小吃（介紹一兩樣），如果不習(xí)慣中餐，可以去KFC。3.交通：從機(jī)場(chǎng)到你所在城市開車大概2個(gè)小時(shí)。建議他做大巴比較便宜，打出租車很貴。4.希望Jack 能多呆幾天，以便你可以帶他游覽風(fēng)景名勝。注意：1.可根據(jù)情況增加細(xì)節(jié)以使行文流暢 2.字?jǐn)?shù)100左右。 3.參考詞匯： T恤和短褲T-shirt and pants 風(fēng)景名勝places of interestDear Jack, I am very excited to know that you will come to China for sight-seeing in April.You want

22、 to know something about my city,now I am wtiting to tell you in detail._學(xué)以致用：根據(jù)提示寫一篇小短文，注意謂語動(dòng)詞形式。34參考范文：Dear Jack, I am very excited to know that you will come to China for sight-seeing in April.You want to know something about my city,now I am wtiting to tell you in detail. It is warm in my city in April,but it can be a little bit hot at the end of this month.Thus you dont