換肚腸

Simplified: 换肚肠

huàndùcháng ㄏㄨㄢˋ ㄉㄨˋ ㄔㄤˊ

    • to turn bad at heart
    • to become treacherous

Character by character

Saying俗语俗語

Idiom惯用语 · Rarely used now

Literally
change one's guts
Meaning
To turn bad at heart; to become mean or treacherous. Critical.

Sources