你永远不我懂伤悲像白天不懂夜的黑
[nĭ yŏng yuăn bù wŏ dŏng shāng bēi xiàng bái tiān bù dŏng yè de hēi]
Means 'You never understand my sorrow like day does not know night’s blackness.' It reflects deep emotional pain that only certain people can understand, comparing understanding sorrow to experiencing darkness.