年少时的海誓山盟就是放屁
[nián shăo shí de hăi shì shān méng jiù shì fàng pì]
Translated as 'Oaths Sworn in Youthful Love are Just Hot Air', it criticizes or mocks the serious promises made in young love as ultimately worthless. This reflects disillusionment or regret over naive commitments made during a period characterized by passionate yet possibly unwise declarations.