小肚鸡肠

xiǎo dù jī cháng

petty; narrow-minded

Character by character

小xiǎo
small

肚dù
belly

鸡jī
chicken

肠cháng
guts

这点小事就生气，你也太小肚鸡肠了。

Getting angry over such a little thing — that’s so petty.

Tone: negative (criticism).

Too small inside to let anything go.

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