悲剧到了头总是喜剧喜剧到了头总是悲剧
[bēi jù dào le tóu zŏng shì xĭ jù xĭ jù dào le tóu zŏng shì bēi jù]
The saying means 'Tragedy turns into comedy when it reaches its end; comedy also turns into tragedy at last.' It reflects on the cyclic nature of happiness and misery, success and failure in life.