情态动词表推测的用法如下:
1、对将来情况的推测,用“情态动词+动词原形”。
She must / may / might / could arrive before 5.
5:00前她一定/可能/也许到。
2、对现在或一般情况的推测,用“情态动词+be”,“情态动词+be doing”或“情态动词+动词原形”。
He must/may/might/could be listening to the radio now.
他一定/可能/也许正在听收音机。
3、对过去情况的推测,用“情态动词 + have +过去分词”。
It must/may/might/could have rained last night.The ground is wet.
地湿了,昨晚肯定/可能/也许下雨了。
注意事项:
情态动词经常出现在虚拟语气之中,尤其是条件句,在虚拟语气的篇章中对此已有涉及。情态动词的过去虚拟式would/should/could/might之后接动词的完成式的用法,需要特别注意,表达的含义是“本来会/本可以/本能够/本应该”等等:
1、I would have told you all about the boy's story, but you didn't ask me.
我本来会告诉你这个小男孩的故事,但是你没有问我。
2、He could have passed the exam, but he was too careless.
本来他能够通过考试,但是他太粗心。