铁打的衙门，流水的官
tiě​dǎ​de​yá​men, liú​shuǐ​de​guān

transience of officials

铁打的衙门，流水的官 (鐵打的衙門，流水的官) tiě​dǎ​de​yá​men, liú​shuǐ​de​guān
transience of officials
The observation that government offices or institutions remain permanent and stable while the individuals who staff them are frequently replaced or reassigned.

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CC-CEDICT