必3unit2Grammar.ppt

人教课标人教课标高一高一 必修必修 3Unit 2Find the sentences containing modal verbs in the reading passage. Then usually by lunchtime they would all be sold. What could have happened? Nothing could be better Something terrible must have happened if He could not believe his eyes.Perhaps he should go to the library and find out.He had better do some research!Even though her customers might get thin after eating Yong Huis food They would become tired very quickly.a. should, ought to 都可表示都可表示“应该应该”。ought to 用于用于表示按道理应当表示按道理应当，常指，常指客客观的义务或责任观的义务或责任，大多数情况下可用大多数情况下可用should 代替，但比代替，但比 should 语气重语气重。I should help her because she is in trouble.You ought to take care of the baby.b. 表示劝告、建议或命令时，表示劝告、建议或命令时，should 和和ought to 可通用可通用，但在，但在疑问句中常用疑问句中常用should。ought to 的否定式为的否定式为 oughtnt to 或或 ought not to。You should / ought to go to class right away.Should I open the window?What should we do next?c. should, ought to 都可表示推测。都可表示推测。He ought to / should be home by now. This is where the oil ought to / should be. should 和和 ought to 后面跟动词不定式的完后面跟动词不定式的完成式成式, 其肯定句表示其肯定句表示“过去应该做而未过去应该做而未做做”, 其否定句则表示其否定句则表示“过去不该做但做过去不该做但做了了”。You should / ought to have made the decision a week ago.I shouldnt have made such a foolish mistake. 多数情况下，多数情况下，ought to 可与可与 should 互换使用。互换使用。ought to 的反意疑问句用的反意疑问句用shouldnt 替代。替代。You ought to have helped him with his English, _?A. wont you B. ought not youC. shouldnt youD. wouldnt you2. must 和和 have tomust 的用法的用法 1) 表示主观的义务和必要表示主观的义务和必要, 主要用于肯主要用于肯定句和疑问句定句和疑问句, 意思为意思为“必须必须，得得，要，要”；由；由 must 引起的疑引起的疑问句，肯定回答要用问句，肯定回答要用 must 或或 have to, 否定回答要用否定回答要用neednt 或或 dont have to, 意思是意思是“不必不必” ； must 的否定形式的否定形式 mustnt 表示禁止，表示禁止，意思是意思是“不能，不许不能，不许”。如：。如： Must I finish the task right now? 我现在必须完成这个工作吗？我现在必须完成这个工作吗？ Yes, you must. / Yes, you have to. 是的。是的。( No, you neednt. / No, you dont have to. 不，不必。不，不必。) You mustnt come here without permission. 未经允许，你不能来这儿。未经允许，你不能来这儿。 have to 的用法的用法 1) must 表示一种主观的需要，而表示一种主观的需要，而 have to 表示一种客观的需要，意思是表示一种客观的需要，意思是“不得不得不不”。 如：如： I have to attend an important meeting this afternoon. 今天下午我不得不参加今天下午我不得不参加一个重要的会议。一个重要的会议。 Mother is out, so I have to look after the shop. 妈妈不在家，因此我不得不照看商店。妈妈不在家，因此我不得不照看商店。 2) have to 的否定形式是的否定形式是 dont have to, 相相当于当于 neednt。如：。如： They dont have to buy a computer at present. 他们目前没有必要买电脑。他们目前没有必要买电脑。 The boss has given everyone a special holiday, so we _ go to work tomorrow. A. cant B. mustntC. neednt D. shouldnt【点拨【点拨】考查情态动词。根据题意考查情态动词。根据题意, 可知可知这里表示这里表示“没有必要没有必要”, 故只能选故只能选C项。项。 What do you think we can do for our aged parents? You _ do anything except to be with them and be yourself. A. dont have to B. oughtnt toC. mustnt D. cant 【点拨【点拨】根据题意根据题意“除了和他们呆在一除了和他们呆在一起做你自己外起做你自己外, 没有必要做任何事情。没有必要做任何事情。” 可知这里选择可知这里选择 dont have to 表示表示“不不必必”。故选故选A项。项。3. must 和和 needa. need 作情态动词时作情态动词时, 只能用于疑问句只能用于疑问句和否定句。构成否定句和疑问句时不和否定句。构成否定句和疑问句时不借助于助动词借助于助动词 do。 Need I finish the work today? Yes, you must. / No, you neednt.b. must 的肯定形式表示的肯定形式表示“必须必须”，否，否定定式表示式表示“禁止、严禁禁止、严禁”。 You must come here. You mustnt take the book away from the library. Choose suitable modal verbs below to complete the following dialogues.ought/oughtnt to should/shouldnt willmustnt neednt (dont) have to can/cant1. Sam: How can I grow thinner, Mum? Mum: Well, you _ eat food with plenty of fibre that helps you digest better. And you _ stop drinking cola or eating sweet food.have to should Sam: Does it mean I _ eat my favourite fried chicken any more?Mum: Not exactly, if you love fried chicken, you _ give it up. Just eat it less often. You _ worry too much: a little fried chicken _ do you good! shouldnt needntdont have to/ neednt/ shouldnt will2. Doctor: You are sick because youve eaten poisonous mushrooms. Where did you get them?Lucy: I picked them in the forest. I know we _ eat fresh vegetables.Doctor: Oh, but you _ eat them until youre sure they are not poisonous.Lucy: Thank you, doctor. Ill be more careful next time.have tomustnt 3. Charles: I wish I could see things clearly in the dark. Tom: Eating carrots _ help you see better. You _ eat some every day.ought to should 从从A、B、C、D四个选项中，选出可以四个选项中，选出可以填入空白处的最佳选项。填入空白处的最佳选项。1. I dont really like James. Why did you invite him? Dont worry. He _ come. He said he wasnt certain what his plans were. (北京北京 2011)A. must not B. need not C. would not D. might not2. I _ worry about my weekend I always have my plans ready before it comes. (上海上海2011)A. cant B. mustnt C. darent D. neednt 3. Hows your new babysitter? We _ ask for a better one. All our kids love her so much. (浙江浙江2011)A. should B. might C. mustnt D. couldnt 4. You _ buy a gift, but you can if you want to. (湖南湖南2010)A. must B. mustnt C. have to D. dont have to5. May I take this book out of the reading room? No, you _. You read it in here. (陕西陕西2010)A. mightnt B. wont C. neednt D. mustnt6. I _ have watched that movie itll give me horrible dreams. (山东山东2010)A. shouldnt B. neednt C. couldnt D. mustnt7. Mark _ have hurried. After driving at top speed, he arrived half an hour early. (天津天津2010)A. neednt B. wouldnt C. mustnt D. couldnt8. When I was young, I was told that I _ play with matches. (上海上海2008春春)A. wouldnt B. needntC. mustnt D. darent9. What sort of house do you want to have? Something big? Well, it _ be big thats not important. (陕西陕西2008)A. mustnt B. neednt C. cant D. wont10. What do you think we can do for our aged parents? You _ do anything except to be with them and be yourself. (重庆重庆2007)A. dont have to B. oughtnt toC. mustnt D. cant11. The boss has given everyone a special holiday, so we _ go to work tomorrow. (上海上海2007春春)A. cant B. mustnt C. neednt D. shouldnt 12. Some aspects of a pilots job _ be boring, and pilots often _ work at inconvenient hours. (湖南湖南2006)A. can; have to B. may; can C. have to; may D. ought to; mustmust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have to用所给的情态动词填空。用所给的情态动词填空。1. You _ go on working because you look so tired now. 2. The weather turned out to be fine yesterday. I _ have had the trouble to carry my umbrella with me. oughtnt to / dont have to needntmust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have to3. If you earn more than 5,000, you _ pay tax. 4. You _ play now! You shall finish your homework first! 5. I know things are hard with you, but you _ try to get over the difficulties.have tomustntmust / have tomust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have to6. I didnt see her at the meeting this morning; she _ have spoken at the meeting. couldnt / cantHomework Finish Using Structures on Page 50 of Workbook.