clean up 动词短语清洗，clean up one's act字面意思清洗某人的行为，引申为过自新、洗心革面、自我检点。

【例句】
My parents said if I don’t clean up my act and get better grades I won’t be able to continue playing football.
我父母说，如果我不改过自新，取得更好的成绩，我就不能继续踢足球了。

Academic probation is a great way to help students clean up their act when they spend too much time partying and not studying.
当学生花太多时间在聚会而不是学习上时，留校察看是一个很好的方法来帮助他们改正自己的行为。