may的否定形式：是cant,mustnt,may not不得

may提问的肯定回答是：Yes,you can.或者,Yes,please.否定回答是，No,you cant.

例句：

In view of this, the decision may not be easy.

考虑到这点，可能很难作出决定。

The list may not be complete.

这个单子可能不全。

I may not have mentioned it to her

我可能没跟她提过这件事。