[英语]情态动词11.pptVIP

You should/ought to have told her the truth earlier. She shouldn’t have left without saying a word. 5).should/ought to have done表示责备或批评,意为“本应该做到…但没有做到…”,用于否定则表示“本不该…但”ought to的语气更强烈. 6. will would 1)用于表意志或意愿 I will never do that again. They said that they would help us. 2)表请求，建议等would 比will 委婉 Will you take a message for him? Would you pass him the book? 3)表习惯性动作，译作“总是；惯于” Fish will die without water. Every evening , he would sit by the window , deep in thought. 4)表功能，译作“能”；“行” This machine won’t work. would表过去反复发生的动作或某种倾向“总是,总要” used to表过去常常（现在已没有这种习惯）“过去常常” used to 可于状态动词连用,would不可以 He used to be a quiet boy. (　　) He would be a quiet boy. (　　 ) Would\be used to √ × * 2. 情态动词的用法特点 1） 情态动词不能表示正在发生或已经发生的事 情，只表示期待或估计某事的发生。2） 情态动词 除 ought 和 have 外，后面只能接不带to 的不定式。3） 情态动词没有人称，数的变化，即情态动词第 三人称单数不加-s。4） 情态动词没有非谓语形式，即没有不定式，分 词，等形式。 只作情态动词的　 can/could, may/might, ought to， must 可情态可实义的　　need, dare 可情态可助动词的　shall/should, will/would 相当于情态动词的　have to, used to 1.Can 的用法： 1）表能力 We can use a computer now. 2)表客观的可能性 It will be sunny in the daytime , but it could rain later on this evening. 3)表“有时候也可能” Even experienced teacher can make mistakes. It can be very cold here, even in July. 3)表请求和允许(could 比can 语气委婉) ---Can I go now? ---Yes, you can. Could you wait a few days for the money? 4)表惊异，怀疑，不相信的态度（主要用在否定句，疑问句和惊叹句中） Can this news be true? How can you be so foolish? 5)can /could 表示推测时，只能用在否定句或疑问句中。 a)It’s so late. Can Tom be reading? b)It can’t be Mary. She has fallen ill. 6)can/could not have done 对过去发生行为的可能性进行推测: I saw him just now so he couldn’t have gone abroad. 7). can/could have done “本可以，本来可能已经”用于肯定句中，表示对过去发生的事情做出的判断， You could have passed the exam. 8) can not \ never ……too…… I can’t thank you too much. I can’t thank you enough. 2.must 的用法 1.must 表示推测时， 只能用于肯定句。 There must be something wrong