一般疑问句中几个情态动词的问与答
例如:You should have come here a little earlier./I ought to have sent him to school./
2.shouldn’t/oughtn’t to+have done,意“本不应该”,含有责备或后悔意。
例如:You shouldn’t have watered the flower./I oughtn’t to have scolded her for such a small thing.
3.might have done,意“过去可能做”;could have done意“本能够做”,两者都含有委婉批评或遗憾之意,也可表对过去情况的推测。
例如:He might have gone to Nanjing with Professor st week,but he was ill.上星期他本可以和王教授一起去南京的,可他病了。We could have finished the work ahead of time.我们本来是能够提前完成工作的。
四、情态动词在反意疑问句中的用法
1.“肯定祈使句+附加问句”结构,附加问句常用will/would/won’t you形式。 例如:Stand still,will/would/won’t you?
2.“否定祈使句+附加问句”结构,附加问句常用will/would you形式。
例如:Don’t watch TV,will/would you?
3.Let’s…,shall we? ; Let us…,will/won’t you?
4.含有must句子的反意问句
1)must表示“必须”时,附加部分常用needn’t,也可用mustn’t.例如:He must go with you,needn’t/mustn’t he?
2)mustn’t表“一定不能”时,附加部分用may.例如:She mustn’t leave,may she?
3)must表“一定、想必”推测意时,附加部分主要有下列几种形式:
A.He must be an engineer,isn’t he?They must be writing now,aren’t they?(这类句子问句前部分含“must be…”或“must be doing…”。)
B.She must have a car/live there, doesn’t she?
C.He must have seen the film,hasn’t he?(这类句子问句前部分的谓语为must have done,句子无具体过去时间状语。)
D.He must have seen the film last week,didn’t he?(这类句子问句前面部分的谓语为must have done,句子有具体过去时间状语。)
E.Mother must have been shopping then,wasn’t she?(前面部分谓语为must have been doing。)
5.含有may表推测的句子,其反意问句形式与must表推测的反意问句形式相似。 例如:She may have finished her homework,hasn’t she?
五、几组词语辨析
1.must与have to:must强调说话者的主观看法,have to强调客观需要,表示“不必”意要用needn’t或don’t/didn’t/won’t have to,不能用mustn’t。
2.can/could与be able to:can多用于现在时,也可用于将来时,could只用于过去时,be able to可用于各种时态。表示“过去经过努力而做成(或没做成)”要用was/were(not) able to ,而不用could(not)。例如:He worked hard,but he wasn’t able to pass the exam.
3.will,would,used to:都可表“习惯”意。①will表示不受时间限制的习惯性动作。如:Fish will die out of water./ She’ll sit for hours without saying anything.
②would表示过去习惯性的动作,但不涉及与现在情况的对比。如:He would walk by the river in the morning.注意:would后不能跟表状态动词。例如不能说He would be late for school last year. ③used to表示过去习惯性的动作或状态,但这种习惯现在已不存在了。如:He used to get up early. He used to be late for school.
4.dare与need