a pleasure which would cost one nothing
It's a Chinese idiom. It's good for others, but it's not bad for yourself. From the Analects of Confucius, Yao Yue.
explain
Giving: benefits; cost: costs. Give others good, but lose nothing.
allusion
Source: The Analects of Confucius, Yao Yue: "because of the interests of the people, is it not beneficial but not costly?" "Wu Taibo family" in historical records: "it's wide but not publicized, and it doesn't cost much."
Example: Sima Qian's historical records Wu Taibo aristocratic family in the Western Han Dynasty: "it's wide but not publicized, it's taking but not greedy, it's place but not bottom."
usage
Used as an object or attribute; used in dealing with affairs.
Chinese PinYin : shī ér bù fèi
a pleasure which would cost one nothing
Every other line is like a mountain. gé háng rú gé shān