turn over a new leaf
Chinese idiom, Pinyin is x ǐ x ī nhu í mi à n, meaning complete repentance, the same as "reform". From the epitaph of Wang Shushi.
The origin of Idioms
According to Qian Qianyi's epitaph of Wang Shushi in the Qing Dynasty, "learning his repeated teachings, out of sincerity, you can't help but wash your heart and take an oath."
Idiom usage
It means to repent completely.
turn over a new leaf
get punished quickly for the evil one has just done - xiàn shì xiàn bòo
pay attention to one 's own moral uplift without thought of others - dú shàn yī shēn
combat the weak with the strong - yǐ duàn tóu luǎn