what did he say? what did he tell you?

问题描述:

what did he say? what did he tell you?
为什么“say”和“tell”不用过去式,“said”、“told”?

do/ did 是助动词,助动词后面的动词(像你说的say和tell) 都是原形,不需要变成过去式.
e.g.What did he do last night
Why did she laugh