Unit 1 Animals on the Farm Lesson 4 Horses and Rabbits 情态动词can,may,must的用法,情态动词后接动词原形; 没有人称和数的变化; 不能单独作谓语, 与后面的动词共同作谓语; 其否定形式在后面直接加not。,Modal verbs 情态动词,can / can not may / may not must / must not,Modal verbs 情态动词,can / can not,1. 表示能力(会) Mary can speak English, but she can not speak French. 2. 表示允许(可以) Can I use your dictionary? I cant find mine. 3. 表示推测 (可能 ) -通常用于否定形式 He cant be in the office. I saw him go out just now.,may / may not,1. 表示允许(可以) May I come in? 2. 表示推测 (可能) -通常用于肯定形式 She may be still waiting for us. 3. 表示祝愿 May you have a happy weekend.,may的用法:,may / may not,以may开头的疑问句，其否定回答用cant或 mustnt。 -May I go home now? -Yes, you may. No, you cant.,may not的用法:,must / must not,1. must表示必须 You must do your homework first. 2. must表示 一定(肯定性推测 ) He must be at home.,must的用法:,must / must not,1. mustnt表示禁止(不准；不允许) You mustnt smoke here. 2. 以must开头的疑问句，其否定回答要用neednt. - Must I clean the classroom now? - Yes, you must. No, you neednt.,must not的用法:,What do the signs mean? Do you know?,You must not cycle.,You must be careful.,You must turn left.,You must not enter.,Can you ? 你会/能吗？,Yes, I can. /No, I cant. 是的，我会/能。/不，我不会/不能。,What can you do ? 你会/能干什么？,I can 我会/能,Can you swim?,No, I cant.,Yes, I can.,Can you play football?,Yes, I can. Its easy!,What can you do ?,I can run fast!,Can you play ping-pong?,Yes,I can.,Thank you!,