外研小学起点 九年级(下) Module 5,英语课件,情态动词,1. can, could,表示能力(体力, 知识, 技能) , 常用情 态动词can和could表达。 Can you lift this heavy box? (体力) Mary can speak three languages. (知识) Can you skate? (技能) 此时可用be able to代替。can只有一般 现在时和一般过去时；而be able to 则有更多的时态。,例如：Ill not be able to come this afternoon. (一般将来时) 当表示“经过努力才得以做成功某事”时应用be able to, 不能用can。如： He was able to go to the party yesterday evening in spite of the heavy rain.,2) 表示请求和允许 -Can I go now? -Yes, you can. / No, you cant. 此时可与may互换。在疑问句中还可用could, might代替，但could, might 并不表示过去式，只是语气更委婉。它们不能用于肯定句和答语中。 - Could I come to see you tomorrow? - Yes, you can. (No, Im afraid not.),3) 表示客观可能性 (客观原因形成的能力)。 Theyve changed the timetable, so we can go by bus instead. This hall can hold 500 people at least.,4) 表示推测 (惊讶、怀疑、不相信的态 度) ，用于疑问句、否定句和感叹句 中。 Can this be true? This cant be done by him. How can this be true?,2. may, might,1) 表示请求和允许。might比 may语 气更委婉，而不是过去式。否定回答时可用cant 或mustnt，表示“不可以，禁止”。 例如： - Might/ May I smoke in this room? - No, you mustnt.,- May/Might I take this book out of the room? - Yes, you can. (No, you cant / mustnt. ) 用May I.？征徇对方许可时比较正式和客气，而用Can I.？在口语中更常见。,2) 用于祈使句，表示祝愿。 例如： May you succeed!,3) 表示推测、可能性 (不用于疑问 句)。might不是过去式，它所表示 的可能性比may小。 例如： He may /might be very busy now. Your mother may /might not know the truth.,3. must, have to,1) 表示必须、必要。例如： You must come in time. 在回答引出的问句时, 如果是否定的, 不能用mustnt (禁止, 不准)，而用neednt, dont have to (不必)。 - Must we hand in our exercise books today? - Yes, you must. - No, you dont have to/you neednt.,2) must是说话人的主观看法，而have to 则强调客观需要。must只有一般现在 时，have to 有更多的时态形式。 例如： His play isnt interesting, I really must go now. I had to work when I was your age.,3) 表示推测、可能性 (只用于肯定的陈 述句) 例如： Youre Toms good friend, so you must know what he likes best. Your mother must be waiting for you now.,用must, have to填空。 1. I know I _ study hard. 2. My mother is ill. I _ look after her at home.,must,have to,1) Please ask that man. He _ know that. 2) The light is on, so he _ be at home. 3) It _ be Wei Fang. She is at school now. 4) Are you coming to Jeffs party? Im not sure. I _ go to the concert instead.,may,must,cant,might,can, may/ might, must 表推测,4. shall和should,征求对方意见,Shall we go out for a walk? What shall we drink?,1) shall,2) should,We should protect our environment. You should do it better next time.,劝告义务责任,用shall/should填空。 1.When _ we meet? 2.You _ see a doctor.,shall,should,5. will, would,1) 表示请求、建议等，would更委婉 例如: Will / Would you pass me the ball, please? 2) 表示意志、愿望和决心 例如: I will never do that again. They asked him if he would go abroad.,3) would表示过去反复发生的动作或某种 倾向。would表示过去习惯时比used to正式，且没有“现已无此习惯”的含义。 During the vacation, he would visit me every other day. The wound would not heal. 4) 表示估计和猜想 It would be about ten oclock when she left home.,should, ought to表示“应该”，ought to 表示义务或责任，比should语气重。 I should help her because she is in trouble. You ought to take care of the baby.,6. should, ought to,2) 表示劝告、建议和命令。should, ought to可通用，但在疑问句中常用should。 You should/ought to go to class right away. Should I open the window?,3) 表示推测 should, ought to (客观), must(主观) He must be home by now. (断定他已到家) He ought to/should be home by now. (不太肯定) This is where the oil must be. (直爽) This is where the oil ought to/should be. (含蓄),情态动词练习,1. 你必须马上回家。 2. 他一定吃过什么东西了。 3. 吃饭之前不能吃零食。,You must go home now.,He must have eaten something.,You mustnt eat snacks before meals.,4. 我可以问你的名字吗？ 5. 你能用英语说吗？ 6. 我们应该准时去上学。 7. 你没有必要那么做。,May I ask your name?,Can you speak in English?,We should go to school on time.,You neednt do that.,问句及否定回答,1. -Dad, must I finish my homework today？ -No, you _. You may finish it tomorrow. (2008朝阳) A. neednt B. mustnt C. dont D. wont 2. -May I put my bike here? (2008广安) -No, you _. You should put it over there. A. may not B. mustnt C. neednt,解答锦囊 掌握情态动词问句的回答： May I? Yes, may. No,mustnt/cant. Must I? Yes, must. No,neednt/dont have to.,表示推测,1. -Is Mr. Brown driving here?(2008安徽) -Im not sure. He _ come by train. A. may B. can C. need D. must 2. -Whos that boy reading in the garden? Is it David? (2008重庆) -It _be David. I saw him in the classroom just now. A. must B. cant C. may D. neednt,3. Im sure this book _ Li Leis, because there is his name on it. (2008吉林) A. cant be B. may be C. might be D. must be,解答锦囊 掌握推测用法:肯定可能性由must may might逐步递减 ; cant则用于否定句、疑问句。,1. -Lisa, _ you speak French?(2008南京) -Yes, but only a little. A. may B. can C. need D. must 2. -_ I use your mobile phone?(2008北京) -Certainly. Here you are. A. May B. Must C. should D. need,基本用法,3. - Mum, can I go to the movies today? (2008长沙) - No, but you _ finish your schoolwork first. A. can B. cant C. must D. neednt,解答锦囊 掌握基本用法: can表能力, may表许可, must表义务。,真题演练,1. -Is Lucy knocking at the door?(2008长 沙) -No. It _be Lucy. She is in Japan. A. neednt B.