1、Period 2 Using languages 1.To get to know some modal verbs.2.To learn how to use modal verbs to make prediction.Learning aims Look at the sentences from the reading passage and answer the questions.a That is why Letters from Father Christmas could be the perfect bookb The children must have been ver
2、y excited as they opened it.c they might not receive their presents if they were not good.Leading-inWhat do the words in red indicate: an order, a request, ability or possibility? 情态动词情态动词must, can/could, may/might均可表示推测均可表示推测, 它们可以对过去、现它们可以对过去、现在或将来的情况作出语气强弱不同的推测。在或将来的情况作出语气强弱不同的推测。1. 把握推测语气的特点。把握推
3、测语气的特点。表示肯定的推测时，各情态动词语气从弱到强依次为表示肯定的推测时，各情态动词语气从弱到强依次为might may could can must；表示否定的推测时；表示否定的推测时, cant / couldnt语气较强，意语气较强，意为为“不可能不可能”；may not / might not语气较弱，意为语气较弱，意为“可能不可能不”。Grammar Modal verbs(2)注意：注意：must的否定形式的否定形式mustnt不表示否定推测，而是表示不表示否定推测，而是表示“不许可不许可”或或“不应该不应该”。2. 基本用法：基本用法：cancouldmaymightmust
4、1.表示能力表示能力eg. I can speak fluent English now , but I couldnt last year.2.在肯定句中，表示客观可能性，并不涉及具体某事会发生，常用来说明在肯定句中，表示客观可能性，并不涉及具体某事会发生，常用来说明人或事物的特征。要表达具体某事实际发生的可能性时，不用人或事物的特征。要表达具体某事实际发生的可能性时，不用can，需用，需用could，may，might。eg. He can be very forgetful sometimes.3.表示对现在的动作或状态进行主观的猜测，主要用在否定句和疑问句中。表示对现在的动作或状态进行
5、主观的猜测，主要用在否定句和疑问句中。eg.Can the man over there be our head master?4.表示惊异、怀疑、不相信等态度，主要用在否定句、疑问句和感叹句中。表示惊异、怀疑、不相信等态度，主要用在否定句、疑问句和感叹句中。eg.This cant be true.5.表示请求和允许。表示请求，口语中常用表示请求和允许。表示请求，口语中常用could代替代替can，使语气更委婉。，使语气更委婉。特别注意：特别注意：（1）could用来表示请求时，语气委婉，主要用于疑问句，不能用于肯定句，答语应用来表示请求时，语气委婉，主要用于疑问句，不能用于肯定句，答语应用
6、用can（即：（即：could不能用于现在时态的简略答语中）。如：不能用于现在时态的简略答语中）。如：Could I use your dictionary?Yes, you can.(否定回答可用：否定回答可用：No, Im afraid not.)(2) can和和be able to辨析辨析can(could)和和be able to都可以表示能力，意思上没有区别。但都可以表示能力，意思上没有区别。但can只有现在式和过去式，而只有现在式和过去式，而be able to则有更多的形式。则有更多的形式。【即学【即学即练即练】1. It was so noisy that we_hear o
7、urselves speak. 2. I_thank you enough for what you have done for me. Youre welcome. 3. 他有可能是我们的老师吗？_?cantcantCan he be our teacher1.表示请求和许可，在疑问句中，表示请求和许可，在疑问句中，might可以代替可以代替may，它表示的语气更加委，它表示的语气更加委婉。婉。知识归纳：知识归纳：may not表示表示“不可；不许不可；不许”时，语气较强，有命令强制的意味，常可用时，语气较强，有命令强制的意味，常可用mustnt代替，用来回答问句代替，用来回答问句“May
8、I.?”2. 表示推测表示推测might和和may表示对现在、将来的推测，多用于肯定句中或否定句中。表示对现在、将来的推测，多用于肯定句中或否定句中。对过去的推测要用对过去的推测要用may/might have done.might比比may的可能性更小。的可能性更小。3. may可以用于祈使句中，表示祝愿，其结构为：可以用于祈使句中，表示祝愿，其结构为：May+主语主语+动词原形动词原形“。May you succeed!祝你成功！祝你成功！【即学【即学即练即练】mightmay1. Helen _ go on the trip with us, but she isnt quite sur
9、e yet.2. I left my handbag on the train, but luckily someone gave it to a railway official. How unbelievable it is to get it back! I mean, someone_have stolen it. 1.表示表示“必须，应该必须，应该”之意，语气比之意，语气比should，ought to强烈。其否定形式强烈。其否定形式mustnt表示表示“不准，不应该，禁止不准，不应该，禁止”等意。等意。eg.Everybody must obey the law.2.在回答带有在回
10、答带有must的问句时，否定回答常用的问句时，否定回答常用neednt或或dont have to，表示，表示“不必不必”，而不用，而不用mustnt。eg.Must I come back before ten? Yes，you must.(No, you neednt.)3.表示有把握的推测，意为表示有把握的推测，意为“一定、准是、一定、准是、想必想必”，只用于肯定句中。，只用于肯定句中。eg.It must be my mother.【即学【即学即练即练】mustmust1. You _ be tired after the long trip, arent you?2. You_be
11、Carol. You havent changed a bit after all these years.3. It _, for the ground is wet this morning.昨天晚上一定是下雨了，因为今早地面是湿的。昨天晚上一定是下雨了，因为今早地面是湿的。must have rained last nightSummary情态动词（情态动词（2 2）基本用法：基本用法：can&couldmay&mightmust语气特征语气特征1. Rewrite the underlined sentences in the conversation using can/could,
12、 may/might and must.Exercise(At a fancy dress party)Chris: I spent ages putting up all the balloons and flowers last night.Jean: I expect you are feeling tired now!Chris: Yes, I am. Look that guy is dressed as Batman. Is that Mike? Jean: Its possibly him. Check out that girl over there. Im sure that
13、s Lucy. Chris: No, I dont think thats Lucy. Lucy isnt that tall.Jean: Look at those two guys dressed as chickens! Oh, theyre waving at us! Maybe theyre from our school.Chris: Lets go and find out.You must feel tired now!It may/might/could be him.That must be Lucy!that cant be Lucy!They may/might/cou
14、ld be from our school.(1) If you _ smoke, please go outside. A. can B. should C. must D. may(2)I dont really like James. Why did you invite him? Dont worry. He _ come. He said he wasnt certain what his plans were. A. must notB. need notC. would notD. might not2. Choose the best answers.(3)The traffic is heavy these days. I arrive a bit late, so could you save me a place?A. can B. must C. need D. might(4)One of the few things you _ say about English people with certainty is that they talk a lot about the weather.A. need B. must C. should D. can
