Grammar Structures for Unit 1 Book III

Modal verbs（情态动词）

教师寄语：Just put one foot in front of the other and God will do the rest.

may / might, can / could, will / would, shall / should, must / can的用法。

1. may 与might的用法

情态

动词 用法 例句 may

与

might

表示允许、许可。否定答语一般要用mustn't，表示"禁止、阻止"之意。 --- May I watch TV after supper?

--- Yes, you may. / No, you mustn't. 在表示请求、允许时, might比 may的语气更委婉一些。在日常口语中，用can征询对方意见更为常见。 ---Might I use your telephone?

--- Yes, please.

--- May / Can I go home now?

--- Yes, you may / can.

表示可能性的推测，含有"或许""大概""可能"之意，用might代替may时，则语气显得更加不肯定。 What he said may be true.

She may come tomorrow.

He might have some fever. 2. can与could的用法

情态

动词 用法 例句

can

与

could 表示能力 Some of us can use the computer now, but we couldn't last year. 表示客观的可能性 It will be sunny in the daytime, but it could rain later on this evening. 表示请求和允许 --- Can I go now?

--- Yes, you can. 表示请求,口语中常用could代替can,使语气更加婉转 Could you wait a few day for the money?

Could you please show me the way to the station? 表示惊异、怀疑、不相信的态度（主要用于否定句、疑问句和惊叹句中） Can this news be true?

It can't be the headmaster. He's gone to Beijing.

How can you be so foolish!