高中英语 情态动词专题讲解课件 新人教版选修7

1、Revision for Modal Verbs,March,2007,诏安一中 高一英语备课组,The basic uses of Modal Verbs,1. Can,Could 过去式；语气更委婉,Can 表示习惯能力， 而be able to表示经过那里而做成了某事。 2. 在否定结构中，二者可以互换。,1.在否定、疑问句中表示“对过去发生行为 的可能性猜测。 2. 在肯定句中表示“本来可以做而未做”,The door was lacked. She couldnt have been at home. You could have been more careful.,1. May,

2、Might 过去式；语气更委婉,1.在否定、肯定句中表示对过去动作的推测 “也许是” 2. Might+have+p.p表示虚拟，表“劝告、责备之意。”,Eg. 1. She may be still waiting for us. 2. May I come in? 3.May you have a happy holiday.,Eg. 1. He might have spoken to her yesterday. 2. You might have told me earlier.,1. Must,表示肯定的猜测,但只用于肯定句， 而mustnt 表示“禁止、不准”,Must表示主观

3、Have to表示客观需求 Have got to 多见于口语,3. must + have +p.p,对过去事情的肯定猜测。,Eg. The road id wet. It must have rained last night.,1、Shall /should,2、shall/should + have +p.p ought to,表示本应该做而未做。,should 过去式 语气更委婉,Eg. You should have been five minutes ago.,Will/ would,1、Would 后只能接表示动作的动词。,2、used to 则还可以接表示状态的动词。 Eg.

4、 He used to be a worker.,1、情态动词用于否定、疑问句；条件从句中。 eg. 1. Dare you go here alone? 2. How dare you do such follish things? 3. I wont allow you to swim in the river, even if you dare do it.,Dare / dared,2 、做实意动词后加不定式。 eg. I have never dared to tell him about it.,Need /needed,1、情态动词用于否定句，疑问句。,2、实意动词用法似dare

5、,用作不定式。,3、need + not + have +p.p 表示“本来不需要做而做了。,Ought to,1、其否定式为ought not to,2、ought to + have + p.p 表示本来应该做而没有做到。,Eg. You ought not to have cut away the trees around the old building.,三点说明,1、情态动词 + v 表示对现在或将来动作的猜测。 情态动词 + have + p.p表示对过去动作的猜测。,2、情态动词的过去式与原形相比，多点礼貌，少点冒昧， 语气更为委婉。,情态动词在一般疑问句中的回答： Can you sing? May I come in? Must I handin the book now? Need I finish it now?,典型错误,1. He mustnt be in the classroom. ( ),Cant,2. You might leave the bag on the bag. ( ),might have left,3. You must have seen the film last week, ha