一、考查情态动词表示"推测"的用法
[考点快忆]表示肯定推测的情态动词有:must"一定;准是",may"也许;可能",might"或许";表示否定推测的情态动词有:can't"不可能",couldn't"不会",may not"也许不",might not"或许不";can表示推测时不用于肯定句,may表示推测时不用于疑问句。
[考例分析]
Susan's parents have bought a large house with a swimming pool. It________be very expensive. (2003上海市)
A. must B. can C. mustn't D. can't
析:mustn't意为"不许;不准",不表示推测;can't意为"不可能",选项C?D均不符合题意,故排除。另外,can在肯定句中不表示推测,而表示"能力"或"许可",也排除?题意为"苏姗的父母亲买了一栋带游泳池的房子",因而可推测出"它肯定很贵"。故选A。
二、考查情态动词引起的一般疑问句的答语
[考点快忆]must引起的问句,肯定答语用must,否定答语用needn't或don't have to;need引起的问句,肯定答语用must,否定答语用needn't。
[考例分析]
—May I try this one on, please?
—________This way, please. (2003湖北省黄冈市)
A. I'm sure you can. B. No hurry. C. Certainly, sir. D. That's all right.
析:选C?对于may提出的请求"许可"时,肯定答语若用"Yes, you may."语气太生硬,而要用"Yes, of course/certainly."等;表示否定用"No, you mustn't."或"No, you can't."。
三、考查情态动词的意义
[考点快忆]must"必须";have to"不得不";need"必须;需要";can(could)"能;可能";may(might)"可以;可能";shall, will(would) "将;会;愿意;要";should"应当"。
[考例分析]
1. —SARS is such a terrible disease.
—Yes, it is. We________be more careful. (2003浙江省舟山市)
A. can B. may C. must D. need
析:"SARS可怕","必须小心"。故选C。
2. You________go and ask Meimei. She________know the answer. (2003天津市)
A. must; can B.must; may C.need; can D.can;may
析:题意为"你可以去问梅梅,她可能知道答案。"故选D。
四、其它
[考点快忆]"had better(not) +动词原形"表示建议;have to/has to/had to的否定/疑问形式要借助于助动词do/does/did。
[考例分析]
1.Look! How heavy the rain is! You'd better________. (2003河北省)
A. don't go now B. stay here when it stops
C. not leave until it stops D. not to leave at once
析:had better后接动词原形,其否定形式为"had better not+动词原形",排除A、D,而据题意应选C。
2. —Please don't make any noise in the reading room.
—________.(2003安徽省)
A. Sorry, I won't B. Sorry, I can't
C. Yes, I won't D.OK, I didn't
析:选A。"Sorry, I won't."意为"对不起,我将不会那样做的。"
