情态动词
一、一般疑问句中几个情态动词的问与答
1. Need I/he/?
Yes, you/he/must. (不用need)
2. Must I/ he/?
No, you/ he/neednt/dont (doesnt, wont) have to. (不用mustnt)
3. May I/ he/?
No, you/ he/mustnt. (少用may not)
4. Could (Can) you?
Yes, I can (不用could)
5. Shall I/she/ he?
No, you(she, he)neednt/cant/mustnt
二、情态动词表推测
1.can,may,must使用的句式:
1)肯定陈述句中:must表肯定、必定、一定意,may/might表也许,或许意。
2)否定陈述句中:cant/couldnt表不可能意,may not/might not表也许不、可能不意。
3)疑问句中:只能用can或could,不能用must, may或might。
注意:表推测的could, might并不是指过去时间,而是表示比can, may把握性略小些的情况。
2.对目前状态的推测:
1)must/may/might/can/could+be+表语
例如:She must be a teacher.她肯定是老师。She cant/couldnt be a doctor.她肯定不是医生。 He may not/might not be a doctor.他可能不是医生。
2)must/may/might/can/could+一些不能用于进行时的静态动词(如:have, exist, live, like, hate, own, belong to等)
例如:She must have her own car, for she has a lot of money.
That kind of bird may live in the valleys.
3.对目前正在发生的事情进行推测:
句式:must/may/might/can/could+be doing
例如:They must be waiting for us.他们肯定正在等我们。
She may/might be doing her homework.她可能正在做作业。
Can/Could he be playing football? 他会正在踢足球吗?
4.对已发生的事情进行推测:
句式:must/may/might/can/could+have done
例如:Theres no light in the room. They must have gone to bed./She knows nothing about the film. She cant/couldnt have seen it./Can/Could he have been a doctor?/He may/might(not)have been a teacher./They must have been watching TV at nine last night./Can/Could she have stayed in Beijing last year?
注意:will have done句式也可表肯定/可能已经推测意。
例如:He will have learned advanced mathematics, for he knows a lot about it. 他肯定/可能学过高等数学,因为他对此懂得很多。
三、情态动词+have done用法
1.should/ought to +have done,意本应该,含有责备或后悔意。
例如:You should have come here a little earlier./I ought to have sent him to school./
2.shouldnt/oughtnt to+have done,意本不应该,含有责备或后悔意。
例如:You shouldnt have watered the flower./I oughtnt 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 Wang. last 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/wont you形式。
例如:Stand still, will/would/wont 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:Dont watch TV, will/would you?
3. Lets, shall we? ; Let us, will/wont 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neednt,也可用mustnt.例如:He must go with you, neednt/mustnt he?
2)mustnt表一定不能时,附加部分用may.例如:She mustnt 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, isnt he? They must be writing now, arent 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, doesnt she?
C. He must have seen the film, hasnt 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, didnt 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, wasnt 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, hasnt she?
上一篇: 高二英语语法学习 表语从句
下一篇: 高考英语定语从句易错题小汇