a fiend of ____(he)

注意

.a friend of his
他的一位朋友
of him 有但 在其他地方用
如
From his briefcase, Mr Li takes out two letter which a friend of him in China told him were urgent.
李先生从他的公文包里取出两封信，他的一位在中国的朋友说这两封信很急。

a friend of his
这里应为代词所有格。

另，括号里如果是
me/I she you Jim(随便谁的名字)
则改为：
mine hers yours Jim's

如果要这样表达的话，用him
没有a friend of his的说法吧，通常都直接说his friend.

his!
这里跟one of my friend可互相转换

him
第三人称 him her them us

his

又如 a friend of mine 我的一个朋友