mine is yellow 这句话为什么不用my,而是用mine呢?

No it is Helen. l left mine at home.为什么用mine而不用my呢 His car is like mine.请问这句话为什么不能写成His car is as mine. He has the same computer as I.这句话中为什么用I而不用mine. Cuz baby you are mine mine(Mine...) Mine mine(Mine...) 这句话中文 this is my skirt(用mine改写) mine it is mine? Oh,there is a picture of mine on the wall.的mine为什么不是my It's mine 后面为什么用mine a friend of mine comes from... 为什么用mine 不用me These English books are mine为什么要用mine不用me All that is yours is rightfully mine! And mine it'll be! 这句话 a hypocrite is no friend of mine.这句话如何翻译呢?