1、Unit7 Topic2 语法专项课件 (情态动词can和could的用法),初中英语仁爱版七年级下册,情态动词用法大观,情态动词三注意: 情态动词表示说话人的语气或情绪 情态动词无人称和数的变化 情态动词后跟动词原形 常见的情态动词: must, can, may, shall, could, might, should, will, would, need等。,can的用法,1. 表示能力时,意为“能、会”。,2. 表示请求或许可时,意为“可以”。,3. 表示猜测时,意为“可能”。,例:He can speak a little Japanese. 他会说一点日语。,例:Can I hel
2、p you? 要我帮忙吗?,例:Where can she go now? 她现在可能到哪里去了呢?,can的句式结构,肯定句:can + 动词原形,否定句:can后加not(缩写为cant),一般疑问句:can提前,He can speak English.,He can not (cant) speak English,Can he speak English?,could的用法,2.表示过去一般的能力,意为“能、会”。,1. 表示委婉请求,意为“可以”。,3. 表示猜测时,意为“可能”。,Could you speak English then?,Could I use your pen
3、?,You could be right, but I dont think you are.,could的句式结构,肯定句:could + 动词原形,否定句:could后加not(缩写为couldnt),一般疑问句:could提前,I could speak English when I was three.,I couldnt speak English when I was three.,Could you speak English when you were three?,易错点1,can 和 could的区别,易错点1,can 和 could的区别,It cant be true.
4、We could go there this summer.,(表推测,can用于否定句),(表推测,不限句式),易错点1,can 和 could的区别,Can I use your pen? Could I use your pen?,(can表请求),(could表更委婉请求),Yes, of course you can.,注意:对请求、允许相关问句的回答,只能用can。,【典例1】_ I borrow your dictionary? Yes, of course you _.A. Can; could B. Could; can C. Can; can D. Could; could,考查情态动词。句意:我可以借用一下你的字典吗?当然可以。表示“委婉请求”选用could,需要用can来回答。故答案选B。,【典例2】That man must be Sarahs husband. No, he _be her husband. She is still single. A. cant B. mustnt C. may not D. couldnt,考查情态动词。句意:那个人一定是萨拉的丈夫。不,那不可能是她丈夫。她是单身。根据句意,表示确切的否定的推测选用cant,答案选A。,