改かい心しん

noun, noun or participle which takes 'suru', intransitive verb

reform oneself; mend one's ways; turn over a new leaf

Refers to a sincere change of heart, often in a moral or behavioral sense. Commonly used with する to mean 'to reform oneself' or 'to turn over a new leaf'.

• 彼かれは悪わるい仲なか間まと縁えんを切きって改かい心しんした。

  He cut ties with his bad friends and turned over a new leaf.