报恩

zhī ēn bào ēn

知恩报恩

know the kindness and repay it

wèi bào ēn

为报恩

out of gratitude

rén shēng zuì tòng kǔ de shì mò guò yú xiǎng qù bào ēn què méi yǒu dì fang

人生最痛苦的事莫过于想去报恩，却没有地方。

The most painful thing in life is to want to return the favor, but there is no place.