交情 (jiāo qing): 우정.

He and I were university classmates; four years of studying together forged a deep friendship between us.

Although we've known each other for a long time, we usually just grab a meal once in a while; our friendship hasn't reached the point where I can ask to borrow money.

Old Zhang is warm-hearted and always offers help when any family has difficulties, so he has a good relationship with all his neighbors.

After graduation everyone went their separate ways and we lost touch, but that friendship has always remained in my heart.

The two of us grew up together and share an extraordinary friendship, so as soon as he asked, I agreed to help.