同甘共苦 tóng gān gòng kǔ

同甘共苦 tóng gān gòng kǔ

解释：甘是甜的意思。共同享受欢乐；共同承担痛苦。

Explanation:
Enjoy happiness and undertake suffering together.

Dialogue:
A：zěnyàng cái suàn shì péngyǒu?
A：怎样 才 算 是 朋友？What can be called friends?
B：tóng gān gòng kǔ de cái suàn shì zhēnzhèng de péngyǒu.
B：同 甘 共 苦 的 才 算 是 真正 的 朋友。Friends should share happiness and sorrow with each other.