如鱼得水

rú yú dé shuǐ

in one’s element

Character by character

如rú
like

鱼yú
fish

得dé
get

水shuǐ
water

他换到销售部以后如鱼得水。

Since moving to sales, he’s been in his element.

Tone: positive (praise).

Liu Bei said that having Zhuge Liang was like a fish finding water (《三国志》).

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