是why not do sth.还是why not doing sth.

why not doing sth还是why not do sth还是why not to do sth why not后面是doing sth还是 to do sth why not do sth why not +do sth 那个语法是why not to do Sth还是why not do Sth 是Why not to do sth还是Why not do sth? Why not doing sth.make sb.to do sth. 是why bot do sth.还是why not to do sth. why not 是加to do sth. 还是 动词原形 why not doing sth和 why not do sth的区别 why not do还是why not doing? Why not doing sth?=___ ___ doing sth?