苦口婆心

kǔ kǒu pó xīn

to urge someone again and again, kindly and patiently

Character by character

苦kǔ
bitter

口kǒu
mouth

婆pó
granny

心xīn
heart

妈妈苦口婆心地劝他别辞职。

His mum kept gently pleading with him not to quit.

Tone: positive (praise).

苦口 = earnest, insistent words; 婆心 = a kindly granny's heart. Usually followed by 劝.

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