why did you say goodbye

why did you say goodbye 请问didn't did don't not或者还有什么的,是怎么个用法比如why didn't you say goodbye 和why don't you say good bye一样吗?都可以这么用吗?谢谢! why are you say什么意思why are you say why did you say 分别什么意思能说出原因吗个位 why did u say it?what did you mean we knew each other before? Why you Say That? What did you say? Whit did you say? You did not say why did you say that ,it seems that you know me well Why did you say that you are unhappy?A B C D 哪个错了Why did you say that you are unhappy?A Why B say C that D are Did you have a good time there yes i did ,By the _____ why did you call me why did you miss Why did you leave why did not you do you have a good memory?why do you say so? bay bay bay why did you say bay bay 这是哪首歌好像是BOA唱的 why do you say that Why do you say that?