why not 是加to do sth. 还是 动词原形

why not 是加to do sth. 还是 动词原形 why not后面是doing sth还是 to do sth 是Why not to do sth还是Why not do sth? 那个语法是why not to do Sth还是why not do Sth why not doing sth还是why not do sth还是why not to do sth 是why bot do sth.还是why not to do sth. 是why not do sth.还是why not doing sth. why not to do sth对吗?waiting why not do sthwhy not to do sthwhich is right why not do sth 等于why dont you do sth 为什么后面要加动词原形呢不是to do 呢 请回答具体一些 why not to do sth 这个结构对吧? why not 加to do吗 why not do sth 还是doing sth why not的英语语法?是不是有wht not do sth = why don't you do sth 那祈使句not to do sth 成立不成立?既有not do sth 又有not do sth 祈使句只有用Dong't开头?我记得以前老师有说Not to....是祈使句... 请问：这两种说法有什么区别?一个是Why don't you do sth.一个是Why do you not to do sth.还有How could you not to do 和 How couldn't you do must 后面是加to do sth.还是do sth. why not后加do还是doing还是to do? 1.want sb to do sth 否定形式?2.help sb do sth 的否定形式又 是什么?3.好像动词不定式否定 是 在不定式之前加not,构成not to do sth.如：tell sb not to do sth但 want to do sth 就是直接用 don't want to do sth 怎么回