为什么单膝跪地是求婚因为双膝跪地是上坟啊
[wéi shén me dān xī guì dì shì qiú hūn yīn wéi shuāng xī guì dì shì shàng fén a]
'Why is kneeling on one knee a marriage proposal because kneeling on both knees is for mourning.' The implication here may have cultural roots but suggests an important life event, such as marriage or funerals, and also adds some dark humor.