|
2017届高考英语考前冲刺精选情态动词 情态动词无人称和数的变化，但却有一定的意义，表示一种看法。英语中的情态动词有: can, could, may, might, shall, should, will, would, must, ought to, need, dare, used to. 1. can 与could 1) 能力： I can do it well. He couldn’t support his family with his few pay. 2) 可能性或允许： She can be free this afternoon. She asked me if she could take the books of the library. 3) 表示惊异、怀疑等： What you told me can’t be true. How can (could) you be so careless! 4) could 可以委婉提出问题和看法，还可以用于虚拟语气中。 Could you give me some help? I would help you if I could. 2. can与 be able to can (could) 表示能力、可能性、允许、迟疑情绪等；be able to 只表示能力，可以有更多的时态形式。 表示能力，二者通用。 I can answer the question. = I am able to answer the question. No one could answer the question. = No one was able to answer the question. I’m sorry. I haven’t been able to answer your letter. 表示可能、允许、推测时用can。 | 
