《新目标英语九年级unit 5 语法 情态动词表推测课件》由会员分享，可在线阅读，更多相关《新目标英语九年级unit 5 语法 情态动词表推测课件（15页珍藏版）》请在金锄头文库上搜索。
1、Unit 5 语法学习,情态动词 must, could, may, might,can,cant 表推测的用法,情态动词表示推测 表示推测的情态动词有must,could,may,might, can等。 它们在表示推测的时候，用来说明说话者的主观看法。 先来看下面的例句，然后补全结论中所缺的内容。 【例句】 Youve had no sleep for 36 hours. You must be very exhausted. 你已经36小时没睡觉了，你一定筋疲力尽了。 2. Dont play with the knife. You could / may / might cut you
2、rself. 不要玩小刀，你会伤了自己。 3. He cant be at home. He has gone to Shanghai. 他不可能在家。他去上海了。,Key: A. 肯定，大 B. might C. cant,【结论】 A. 当must表推测时，一般只用于_ (肯定/否定)句，意为“肯定、一定”。它的肯定程度比could, may, might _ (大/小)得多。 B. could, may与_均可表示把握性不大的推测，意为“可能、也许”。 C. 表示否定推测时常用_，意为“不可能”。切记不要用mustnt。,肯定,大,might,cant,must,cant,could m
3、ight,100% probably true,20%-80% possibly true,0 % almost not true,用情态动词表示讲话者对客观事物的主观看法，这就是情态动词 的推测性用法。 一般来说，英语中可以用于表示推测或可能性的情态动词有can, cant, could, may, might 和must。 1. must表示推测时，暗含发生的可能性很大，它的肯定和程度比 may, might, could大得多。例如： You must be very tired after the long walk. 走了这么长的路，你一定很累了。 在must之后还可用不定式的进行式
4、或完成式表示对正在发生事情或 已经发生的事情的推测。例如： You must be joking. 你一定是在开玩笑吧。 He must have learned English before. 他以前肯定学过英语。 must 表示推测时通常只能用于肯定句，若要表示否定的推测， 要用cant, 而不能用mustnt。 例如： She cant have heard the news. 她不可能听到这个消息。,2. can 表示推测时，常用在否定句、疑问句和感叹句中，表示惊异、 怀疑、不相信等情态意义。could表示的可能性比can小些，且比can 的语气更委婉，二者没有时态的差别。在过去时态中
5、，could也可表 示过去的可能性。例如： Can it be true? 会是真的吗？ It cant be true. 它不可能是真的。 Anybody can make mistakes. 任何人都可能会犯错误。 It could rain tomorrow according to the radio report. 据电台报道，明天可能会下雨。,3. may 和might表示推测时，可表示现在或将来的可能性，通常用 于肯定句，might表示的可能性比may小些，在过去时间的语境中， might也可表示过去的可能性。例如： He may come tomorrow. 他明天可能会来。
6、It may / might rain tonight. 今天晚上可能会下雨。 They may / might be having a meeting in the classroom. 他们可能正在教室里开会。 If I were lazy, I might fail. 如果我懒惰，我可能会失败。 He may / might have missed the bus. 他可能没有赶上那辆公共汽车。,4.含有表推测的情态动词的句子的反义疑问句,1.若must表示推测，疑问部分不能用must，而应根据must后的动词结构采用相应的动词形式： He must be tired, isnt he?
7、 他一定累了，是吗?2.当must用来表示对现在的情况进行“推测”时，反意疑问部分要根据must后面的动词采用相应的形式。 例：He must be good at maths, isnt he? 他数学一定学得很好，是吗？ 3.当must用来表示对过去的情况进行“推测”（must + have done）时，如强调对过去情况的推测（一般句中有过去的时间状语），反意疑问句部分要用“didnt + 主语”；如果强调动作的完成（一般没有过去时间状语），反意疑问句部分要用“havent / hasnt + 主语”。 例：She must have read the novel last week,
8、didnt she? 她上星期一定读了这本小说了，是吗？ You must have told her about it, havent you? 你一定把这事告诉她了，是吗？,Learn to make inference,巧记乐记 must句中表推测，表示某事会必定； might,could来推测，语气不如must； 否定推测“不可能”,只有cant才能行。,Grammar,【运用】1 选择最佳选项。 ( )1. Susans parents have bought a large house with a swimming pool. It _ be very expensive. A.
9、 mustB. canC. mustntD. may not ( )2. Henry _ be at home because he phoned me from the farm just now. A. mustntB. isnt able to C. may notD. cant ( )3. Whose red backpack is this? It _ be Toms. His backpack is red. A. mightB. needC. mustD. cant,( ) 4.Look at the boy running on the ground. Is it Davis?
10、 It _ be him. I saw him go to the teachers office just now. A. must B. cant C. could D. might,( ) 5.Even the top students in our class didnt work out the problem. So it _ be very difficult. A. need B. must C. cant D. shouldnt,( ) 6. - Excuse me. Where is the zoo? - Sorry, I dont know. Ask that polic
11、eman. He _ know. A. shall B. may C. need D. would,( ) 7. - Tom, where is your father? - Im not sure. He_ in his office. A. is B. may be C. maybe D. may,8.What is your mother going to do this Saturday? -Im not sure.She_go to see my grandmother. A.canB.mustC.may 9.-Look, Sue is over there. -That _be h
12、er. She is in Canada now. A. mustnt B. cant C. neednt D. wont 10. Whose notebook is this? - It _ Tom. I saw he used it just now. A. must belong toB. cant belong toC. might be belonged to 11.The lake is said to be dry.Is that ture? -It _.Look ,some kids are swimming in it. A.must be trueB.cant be tru
13、eC.may not be true 12.Look at that girl! Is it Susan? -No, it _ be her. She has gone back to her hometown. A. mustnt B. cant C. neednt D. wouldnt 13 .The winner of the race is a tall and thin boy with glasses. -Then it_be my friend,Mike,who looks like very fat. A.mightB.cantC.dontD.should,2.Exercise
14、s: Complete the sentences using“must”or“cant”. 1. I have tried to call him at the office, but there is no reply. He _be at home. 2. They have bought a new car. They _have a lot of money. 3. She is carrying a Japanese newspaper. She_ be Chinese. 4. He goes abroad a lot, He _have an important job. 5. She is a professor at the university. She _be very clever. 6. She is acting in a Shakespeare play tomorrow. She_ be an actress.,cant,must,cant,must,must,must,1.预习34-38(p148-149)页的生词。 2.完成讲学稿和课时练上的课前准备练习部分。 3.复习本节课的语法。,Homework,
