三心二意

sān xīn èr yì

half-hearted; in two minds

Character by character

三sān
three

心xīn
hearts

二èr
two

意yì
minds

做事不能三心二意。

You can't do things half-heartedly.

Tone: negative (criticism).

Opposite of 一心一意; also used for being fickle in love.

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