人教版英语九年级全册练习题：Unit 8 It must belong to Carla3 单元语法小专题.doc

1、单元语法小专题(Grammar Focus)语法精讲情态动词表示推测的用法1对不同时态的推测本单元主要学习情态动词must，can/could，may/might表示推测的用法。表示推测时，要根据肯定、否定或疑问的不同句式选用不同的情态动词。“情态动词do sth.”表示对现在事物的推测；“情态动词be doing sth.”表示对正在发生的事情的推测；“情态动词have done sth.”表示对过去或已完成事情的推测。如：They must be in the classroom now.他们现在一定在教室里。Peter may/might have been hurt in the ca

2、r accident.彼得可能在车祸中受了伤。2肯定推测(1)must用于肯定句，表示较有把握的推测，意为“准是，一定”，后面接动词原形，表示对现在的推测。如：Ive had no sleep for 48 hours.我已经48小时没睡觉了。You must be exhausted.你一定筋疲力尽了。(2)may用在肯定句中，表示对现在把握不大的推测，意为“也许，可能”。如：It may be a new species.它可能是一个新品种。(3)could，might也可表示推测，常用在过去时中；但在某些场合下，为了使语气更委婉，常用could，might代替can，may。如：They

3、 saw something in the sky last night.It could/might be a UFO.昨天晚上他们看见空中有个东西。它有可能是不明飞行物。You might/could be very tired.你可能很累吧。(4)can用在肯定句中，表示理论上的可能性。如：Smoking can cause cancer.吸烟有可能引发癌症。3否定推测(1)表否定推测时，cant/couldnt语气最强，指“不可能”，带有惊异、怀疑的感情色彩。如：The story sounds reasonable，but it cant be true.这个故事听起来合情合理，但不

4、可能是真的。(2)语气不是很肯定时，常用may not或might not表否定推测，意为“可能不，也许不”。如：He may/might not be at home.他可能不在家。4疑问句中的推测疑问句中的推测，常用can或could，意为“可能”。如：Who can it be？Can it be Jenny？那可能是谁呢？是珍妮吗？语法精练.用must，may，might 或cant 填空。1The textbook must_be his.It has his name on it.2The beautiful trousers cant be Jims.They are too l

5、ong.3The large shoes cant be Marys.She has small feet.4The football might/may_be Wei Huas or Tian Huis.They both play football.5The guitar must/may belong to Sam.He often plays the guitar.6I cant find my pen.It must/might be left at home.7The red bike cant be his.His is black.8Listen! Is Tom singing

6、 in the classroom?No.It cant_be Tom.He has gone to Paris.9Where is Jane?She may be in her bedroom，but I am not sure.用must，might，can，could或cant完成下面对话。A：Tina，you look worried.Whats wrong?B：I cant find my English book.Where _10_ it be？I _11_ have lost it.A：Dont worry.Lets see where it _12_ be.B：I think I _13_ leave it in the reading room.But it isnt there.A：What does your book look like？Lets look for it together.B：Its blue.A：Oh，look！Is this one yours?B：No.It _14_ be mine.Toms name is on it.A：Im afraid you have to buy a new one.10can11.must12.could13.might14.cant