题目内容：

what did you say 和 what did you said 的区别
不是过去是吗?为什么大家用what did you say而不用what did you said

优质解答

因为did是表示过去式的,助动词用了过去式,动词就得用原形
在疑问句和强调句中才会有助动词提前的情况,其他时候都是直接用动词过去式的
比如：He visited his uncle yesterday. (普通过去式）
He did visit his uncle yesterday. （强调）
Did he visit his uncle yesterday? （疑问）