第一讲 情态动词 Step1 Lead in 1. Show some pictures and then answer the questions below the picture. The boy has been playing computers for three hours, what must the boy do now?What can she do?The room is in a mass. What shall the students do?2.List those modal verbs used in the above sentences.Step2 Presentation一、情态动词的特点：1、情态动词不能单独做谓语2、情态动词+V.原形3、没有人称和数的变化二、情态动词的基本用法：1、 can, coulde.g. He can speak English now, but he couldnt speak English two years ago. Can this green bike be Toms? You can (may) go home now. Could you come again tomorrow? He will be able to do the work better.2、may, mighte.g. - May I use this dictionary? - Yes, please. / Certainly. / No, you mustnt / cant. They may (might) be in the library now.3、shall, should, ought to shall的用法主要体现在不同人称时的不同用法：e.g. Shall we go now?Shall I open the door? You shall fail if you dont work hard.【练习】 (2007四川高考）-What does the sign over there read? - “No person _ smoke or carry a lighted cigarette, cigar or pipe in this area.” A. will B. may C. shall D. mustshould和ought toe.g. He should take care of his parents.Such things ought not to be allowed. You should be so rude to a lady. Why should you be so late?【练习】(2006江苏高考）-I think Ill give Bob a ring. -You _ . You havent been in touch with him for years A. will B. may C. have to D. should4、will, woulde.g.Will you have some more wine?Would you mind my smoking here?Fish will die out of water.When I was young, I would play badminton on Sundays.I will never do that again.三、情态动词的特殊用法表推测1、可以表示推测的情态动词mustcan (cant) could (couldnt)may (may not) might(might not)注意：could和might并不是can 和may的过去式，它们仅仅强调可能性的大小2、对不同时间的推测的表达对现在或将来的推测：情态动词+V.原形 情态动词+be +doing (正在进行)对过去的推测：情态动词+have done 情态动词+have been doing （过去正在进行/一直在做）情态动词适用形式适用时态意义语气轻重must 只用于肯定句must +domust+be doing must+have done一定，肯定语气最重can/ could 常用于疑问句和否定句cannt/couldnt+docannt /couldnt+be doing cannt /couldnt +have done可能，能够语气次之may/ might 可用于肯定句、否定句和疑问句may/ might +domay/ might +be doing may/ might +have done也许，可能语气最轻【练习】1).You _. Youve just had dinner. (be)你不可能又饿了。你刚刚吃完饭。2). She knows this place so well. She _here. (live)她非常了解这个地方。她一定在这里住过。3). Lets hurry. He _ at the station when he arrives. (wait)我们快点。他到了就可能在车站等我们。4). We didnt find him. He _. (go)我们没有找到他。他有可能走了。5). - Guess what! I have got A for my term paper.猜怎么了！我这学期考试得了A。 - Great! You _widely and put a lot of work into it. (read)太好了！你一定阅读得很广泛，并且投入了很多。6). Shes hard-working girl. Since she is not studying in the classroom, she _in the library now.她是一个勤奋的女孩。因为她现在不在教室学习，她肯定现在在图书馆读书。7). I didnt see her in the meeting room this morning. She _ at the meeting. (speak)我今天早上没有在会议室看到她。她不可能在会议上发言了。重难点训练重难点一级训练之选择题情态动词的基础练习1. -Mum， may I watch TV now？- -Sure， but you _ help me with my English.A. can B. may C. must D. could2. -_ I download the article again？ -No，you neednt.A. Shall B. Will C. Must D. Can3. -Can you go skating with us this afternoon？-Sorry， I cant. I _ take care of my little sister at home.A. can B. may C. would D. have to4. -Must I hand in my exercise book today？-No， you _.A. cant B. neednt C. mustnt D. wont5. -May I have a word with you？-No， you _. Im busy today.A. neednt B. wouldnt C. dont have to D. cant6. -_I have your English name， please？-Yes， Helen. H-E-L-E-N.A. Must B. May C. Will D. Need7. -Who is the boy over there？ Is it John？-No， it _ be him. John is much taller.A. mustnt B. may not C. cant D. neednt8. -Can you play Frisbee， Jay？-Yes， I _. Its easy.A. must B. can C. need D. may9.-You must come back every month. -Yes， I _.A. will B. must C. should D. can10. She _ know the answer， but Im not sure.A. maybe B. may be C. may D. must11. - Must we clean the room right now？- No， you. You clean it after lunch.A. neednt；may B. neednt;must C. Mustnt； can D. mustnt；may12. John_ come to see us tonight， but he isnt very sure yet.A. may B. can C. has to D. must13. Children _ play with fire.A. mustnt B. cant C. shouldnt D. neednt14. -_ I c