why don't you

你为什么不和我们一起来呢？

___Why ___don't ___you come with us?

你为什么不给我拍张照呢？

___Why ___don't ___you take a picture of me?

你为什么不给你奶奶带些花呢？

___Why ___don't ___you take some flowers to your grandmother?