江山易改，本性难移
jiāng​shān​yì​gǎi, běn​xìng​nán​yí

innate nature

江山易改，本性难移 (江山易改，本性難移) jiāng​shān​yì​gǎi, běn​xìng​nán​yí
innate nature
It is easier to change mountains and rivers than to alter one's character; an idiom suggesting that one's fundamental nature or personality is very difficult to change.

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