钻坚仰高
zuān​jiān​yǎng​gāo

diligent study

钻坚仰高 (鑽堅仰高) zuān​jiān​yǎng​gāo
diligent study
to delve deeply and meticulously into one's studies or research with great effort and persistence
profundity
describing the profound and inexhaustible nature of a great master's teachings or character, such that the more one studies it, the deeper it seems

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