Definition
Used to describe people who have known each other for a considerable amount of time.
認識很久
He and I go back a long way; we've known each other since childhood.
他和我認識很久了，我們從小就認識。
Those two go back a long way, which explains their deep bond.
那兩個人認識很久了，這解釋了他們深厚的感情。
Our group of friends goes back a long way; we've known each other since our university days.
我們這群朋友認識很久了，從大學時期就認識了。