兢兢业业

jīng jīng yè yè

conscientious and hard-working

Character by character

兢jīng
careful

业yè
diligent

他在这个岗位上兢兢业业工作了三十年。

He worked conscientiously in this post for thirty years.

Tone: positive (praise).

From the Book of Documents and the Book of Songs, where it meant 'cautious and fearful'; now praise for steady, diligent work over many years.

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