1、情态动词(2)一、may/might观察例句Might I ask for a picture of your little daughter?Yes，you may.We may go to the cinema tonight，but we are not sure yet.May you be happy every day!There is nothing to do，so I may as well go to bed.归纳用法1表示请求、许可。在疑问句中用might比may的语气更委婉。2表示推测意为“可能、或许”。might比may语气弱。3表示祝愿，常用结构为“May主语动词原
2、形！”4may/might as well表示“不妨”。即学即练1用适当的情态动词填空May/Might I take the book out of the library?He may/might come back in an hour，but Im not sure.Now that you have come，you may/might as well stay.May you enjoy yourself!二、shall/should/ought to观察例句Shall I buy some picture books for the children？Shall Tom go t
3、here with me tomorrow?You shall finish your homework first before you go out and play.One of our rules is that every student shall wear school uniforms while at school.You should/ought to put more effort into your work.She promised to come by 10 oclock.She should/ought to be here at any moment.Its n
4、ot surprising that people should be suspicious of politicians promises.归纳用法1shall用于第一、三人称的疑问句中，征求对方的意见。2shall用于第二、三人称的陈述句，表示说话人给对方的命令、警告、允诺或威胁；此外，当颁布法律、规定时也用shall。3should/ought to都表示劝告和建议，意为“应该”，此时ought to比should语气要强。4should/ought to都表示预测可能性，意为“按道理应该会”。5should表示惊讶、意外等情绪，意为“竟然”。即学即练2用适当的情态动词填空Shall w
5、e put off the sports meet till next week?You shall receive all the money that is owed to you.We should/ought to be strict with ourselves.He left Paris in the morning.So he should/ought to arrive here by supper time.It is strange that such things should happen in our school.三、will/would/used to观察例句If
6、 you will read the book，I will lend it to you.Would you come into the bar and have a drink with me?Every evening he will have a walk along the river.I still remember my happy childhood when my mother would take me to Disneyland at weekends.He used to spend all his money on food and drink; now he liv
7、es a simple life.归纳用法1will/would表示意愿，可用于各种人称。2will/would表示“请求；建议”，此时would比will更委婉。3will/would表示习惯，意为“总是，习惯于”。与used to相比，would表示过去重复、习惯性动作；而used to则强调过去与现在的对比。即学即练3用适当的情态动词填空We will never give up working，whatever happens.Would you mind opening the window for me?He will talk for hours if you give him
8、the chance.Last year our English teacher would tell us stories in English after class.I used to smoke，but I gave up a couple of years ago.四、“情态动词have done”观察例句Since nobody gave him any help，he must have done the research on his own.He cant have gone to Shanghai，for I saw him a minute ago.He might ha
9、ve said so at the meeting，but Im not sure.You could have done better，but you didnt try your best.I was really anxious about you.You shouldnt have left home without a word.You neednt have told him the news; he has heard it already.归纳用法1表示对过去的推测(1)must have done表示对过去发生的事情十分肯定的推测，意为“一定做过某事”。(2)can/coul
10、d have done用于否定句和疑问句，表示对过去发生的行为的怀疑和不肯定，意为“不可能已经”或“可能已经了吗？”(3)may/might have done用于肯定句和否定句，表示对过去发生某事的可能性的推测，意为“或许做过某事”或“或许没做过某事”。2表示后悔、责备或遗憾等情绪(1)can/could have done用在肯定句中，表示对过去没有实现的可能性的遗憾，意为“本来能做实际上却未做”。(2)should/ought to have done表示本该做某事而实际上未做；否定式表示本不该做但却做了。(3)neednt have done表示做了本来不必做的事。即学即练4完成句子昨
11、晚一定下雨了，因为地面还是湿的。It must have rained last night，for the ground is wet.他或许会多给你一些帮助，即使他很忙。He may/might have given you more help，even though he was busy.他本来能通过考试，但他太粗心了。He could have passed the exam，but he was too careless.你本没有必要来学校。今天是周日。You need not have come to school.It is Sunday today.现在太晚了。那时你本该抓住机会的。Its too late now.You should have grasped the chance then.