However, they did not officially contact the men and women, and finally became a common friend.

但他们并没有开始正式的男女交往，最后成了普通朋友。

youdao

youdao

We happened to discover we had a friend in common.

我们碰巧发现我们有个共同的朋友。

《柯林斯英汉双解大词典》

It is to assert the common humanity of us all: "That's what I call a friend."

它指出了我们共有的人性：,“朋友就要互相帮助“

耶鲁公开课 - 文学理论导论课程节选

Around that time Kerns met Ma at a poker game set up by a common friend.

FORBES: Picking Winners

During that time, a member of the capitalist class, Andrew Carnegie, argued the opposite: that, in fact, a sound currency was the friend of the common man, while a floating currency often gave speculators and financial sophisticates an unfair advantage.

FORBES: Ask Greek Citizens About Soft (Drachma) Money, And If They Like It

Just as important, the different humans who knew a particular animal agreed about its personality to a degree similar to that found when several people describe a human friend they have in common.

ECONOMIST: Animal behaviour