放肆的青春诠释谁的悲伤
[fàng sì de qīng chūn quán shì shéi de bēi shāng]
It suggests a wild youth defining whose sorrow it represents - perhaps suggesting everyone experiences a reckless youthful phase full of trials and tribulations. In short, these unrestrained, tumultuous days of youth are filled with various experiences and sentiments such as sorrow.