用may或may be填空：She ( ) know the answer to this math problem,but I'm not so sure.
问题描述：
用may或may be填空：She ( ) know the answer to this math problem,but I'm not so sure.
答
may.
know是动词,不能直接跟在BE后面.实在要就要变为被动,不过感觉逻辑不对
PS:maybe那么两个都可以