情态动词情态动词 的用的用法法1 、 Could I borrow your book
Of course you can
Would you like to do it for me
I would
一、情态动词注意事项(1) 对现在或将来情况推测: must + 动词原形
must 只能用于肯定
否定和疑问分别用 can’t和 can
He must tell a lie
Can he tell a lie
He can’t tell a lie
*Must-should/ought to –may-might/could+do可能性依次减弱2 、推测语气(2) 对过去情况推测: must (may, might)+完成时
You must have met him before
must—may—might 可能性依次减弱must 只能用于肯定句,译成“一定”
否定和疑问分别用 can’t / couldn’t 和 can / could
Could /Can it have happened last night
It couldn’t/can’t have happened last night
He must be reading, isn’t he
You must do it yourself, don’t you
He must have gone over the article, hasn’t he
It must have rained last night, didn’t it
3 、表猜测语气的反意疑问句的构成 would need used to do dare mustn’t don’t have to=needn’tmay/might do/have done不妨… ; 还是…为好4 、 be a