A man must eat a of salt with this friend before he knows him啥意思?

问题描述:

A man must eat a of salt with this friend before he knows him啥意思?

朋友只有共患难过才能知道他是不是真的朋友.
个人感觉应该是这个意思,呵呵,不过前面半句...a of...是不是打错啦?