太美的承诺因为太年轻苍白的微笑因为太无耐
[tài mĕi de chéng nuò yīn wéi tài nián qīng cāng bái de wēi xiào yīn wéi tài wú nài]
This phrase means 'Promises were too beautiful because we were too young; smiles turned pale out of helplessness'. It laments lost youth and unfulfilled promises due to the immaturity and helplessness of young love.