中考英语情态动词与助动词难点例析
I． 要点　助动词本身无意义，在句中帮助主要动词构成一定的时态，语态、语气，或是帮助构成否定句和疑问句，常用的助动词有be, do, have, shall(should), will(would).　情态动词表一定的词义，本身并不表示动作或状态，而仅仅表达说话人的态度，它在句中须和主要动词一起构成谓语，主要的情态动词有can(could), may (might), must, have to, ought to, need, dare, shall, should, will, would.　1、can 能，可以，表说话人同意，许可还可表客观条件许可，如:You can go now.　提建议或请求时可用can I, can you表客气，如Can I buy you a drink?　can和be able to表能力时的区别。　can表一般具有的能力，be able to表在特定条件下的能力，如:Although the driver was badly hurt, he was able to explain what had happened.