题目内容：

You don't need to know who the girl standing over there is,but if you _____ know,her name is Jenny
选择：may can must shall
答案must 求详解

优质解答

You don't need to know who the girl standing over there is,but if you _must_ know,her name is Jenny
你不需要知道站在那边的女孩是谁,但如果你一定要知道,她的名字叫珍妮.
呵,比较婉转的“不关你事,问来做什么”的说法.
因为前面已经说了你不需要知道,所以后面就用must,必须了.
may 是可以
can 是能够
shall 是应该
都不配合前文.