Unit 2 Let's Celebrate! Using language 情态动词课件-2023-2024学年高中英语外研版（2019）必修第二册

1. 有词义,情态动词后 + do,被动时用 be done 否定形式为情态动词 + not 2. 通常没有人称和数的变化 1. That is why Letters from Father Christmas could be the perfect book... 2. In another letter,Father Christmas complained about how he could not stop his helpers... 3. ...we can all share the true spirit of giving at Christmas time. 4. Interestingly,the letters did not contain the usual warnings to children that they might not... 5. The children must have been very excited as they opened it. 6. The letters were also beautifully illustrated—each must have taken its true author... Unit 2 语法回顾 表能力 表可能性 表猜测,“一定已经发生了” 1. 表示能力 eg. My granny can do some shopping on the Internet, but she couldn’t last year. 【辨析】 ① can 一般指自身具有的能力, be able to 则表示经过一段时间的努力后所具有的能力, 相当于manage to do或succeed in doing。 eg. This time I failed in the exam, but I’ll be able to pass the exam next time. can,could,be able to 语法精析 ②现在时can与be able to没有区别,但是在过去时中二者意义不同。 eg. I can/am able to speak both English and French. eg. All the people could escape from the burning hotel last night. 昨晚所有的人都有能力从燃烧的旅馆里逃脱出来。(有这种能力,但不一定做到) All the people were able to escape from the burning hotel last night. 昨晚所有的人都从燃烧的旅馆里逃脱出来了。(成功做到了) 2. 表猜测,意为“可能”,一般用于疑问句和否定句 eg. Can this news be true? 3. 表示请求和许可(could表示更委婉的语气,回答时只能用can) eg. — Can/Could I go now? —Yes,you can. 4. 用于肯定的陈述句中,表示理论上或习惯上的可能性。 eg. As we all know, anyone can make mistakes. 5. can/could表示惊讶,常用在否定句和疑问句中。 eg. How could you do such a silly thing?(表示惊讶) 6. 习惯用法“cannot...too...”, 有时cannot可用can never替代。 表示“无论怎样……都不过分,越……越好” eg. We cannot thank you too much for what you’ve done for us. may might 1. 表示允许、许可。might在语气上比may更委婉。 以may/might开头的问句在否定回答中要用mustn’t/can’t。 eg. —May/Might I play the computer games after supper? —Yes, you may. / No, you mustn’t/can’t. 2. 表示把握不大的推测,意为“可能”,用于肯定句。 might 语气更加不肯定,指现在或将来, 只有在宾语从句中 might do (be) 才表示过去的可能性。 eg. I think he may come tomorrow. He told me he might be late. may, might 语法精析 3. may用于祈使句表示祝愿。 eg. May you succeed. 4. 习惯用法:may/might as well,表示“最好还是……,不妨” eg. If no one els