专题05 情态动词（讲解）-备考2021年高考英语语法分类讲解+十年真题解析

一．定义：情态动词是一种本身有一定的词义，表示说话人的情绪、态度或语气的动词，但不能单独作谓语，只能和其他动词原形构成谓语，没有人称和数的变化。有助动词的作用，可构成否定和疑问。 He may tomorrow. ( ) I may come tomorrow. He mays come tomorrow. ( ) He can speak English. He can speaking English. ( ) —Can you sing？ —No, I can’t. 二．“全家福” 情态动词 情态动词短语 现在式 过去式 can could be able to may might be allowed to must   have to will would be going to shall should be supposed to/ought to need/dare 3． 基本用法 1. can/could (be able to)的用法 can 现在能力 Tom can run very fast. 请求 征求对方意见 Can I help you? 有时会 Tom can be very annoying sometimes. Peter can be really difficult at times even though he's a nice person in general. 可以 （客观条件允许做某事） A left-luggage office is a place where bags can be left for a short time could 过去能力 Tom could run very fast when he was young. （委婉客气）请求 Could you help me? 建议 怀疑（疑问推测） We could go shopping. Could this be true? 可以 （客观条件允许做某事） When I was a child, I could watch TV whenever I wanted to. 2. must/mu