雷厉风行

léi lì fēng xíng

swift and decisive

Character by character

雷léi
thunder

厉lì
fierce

风fēng
wind

行xíng
move

新经理雷厉风行，一上任就改了好几项制度。

The new manager moves fast — he changed several rules as soon as he started.

Tone: positive (praise).

Acting like thunder and wind; 行 is xíng.

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