一. may可以用来表示
1.(可不)可以：
May I ask you a question?
我能问你一个问题吗?
You may go now.
你现在可以走了。
2.可能，或许(表推测)：
She may not be at home now.
她可能不在家。
He may have gone abroad.
他可能出国了。
I may be late for a few minutes.
我可能会迟到几分钟。
may也可以用在表示目的等的状语从句中(a)或用来表示祝愿(b)：
1) Write to her so that she may know our address.
给她写封信址让她知道我们的地址。
2)May you have a long and happy life!
祝你幸福长寿!
二.might可用作may的过去式表示：
1.可以：
He a sked whether he might use our phone.
他问可否用我们的电话。
He thought he might have a try.
他想他可以试一试。
2.可能，或许：
I thought mother might like the idea.
我想妈可能会赞成这个想法。
She was afraid he might not agree.
她怕他或许不赞成。
might也可用来代替may，使口气显得更委婉或不肯定，表示：
1)可以：
Might I have a cup of coffee?
我可否要一杯咖啡。
You might sit by my side.
你可以坐我旁边。
2)可能，或许：
The paper says that it might rain.
报纸说可能要下雨。
She might have forgotten about it.
她或许忘了这件事。
此外还可用在某些从句中(a)或条件句中(b)：
a. He died so that others might live.
他死了使别人能活下来。
b.If I were her，I might agree.
如果我是她我可能会同意。
