我的过去他被狗吃了
[wŏ de guò qù tā bèi gŏu chī le]
In Chinese slang, this means 'forget about the past'. Literally it says 'my past was eaten by a dog', implying that the person doesn't want to recall or is unable to recall certain parts of their past, suggesting either indifference or pain regarding history they've gone through.