Who told you that?这个句子对吗 这个疑问句为什么不用助动词 是不是当疑问句的时候 疑问代词是做主语时

Who told you that?这个句子对吗 这个疑问句为什么不用助动词 是不是当疑问句的时候 疑问代词是做主语时
不需要助动词啊 是不是只是疑问代词做主语才不需要助动词啊

Who told you that?这个句子是正确的.当疑问词作主语或主语的定语时,其后直接跟动词作谓语,不需要再加助动词.
例如：
(He) is a teacher.试比较：
Who is a teacher?
The boy (under the tree) is Li Ping.
Which boy is Li Ping?
(They) went to Beijing last year.
Who went to Beijing lasr year?
(My) father has a new car.
Whose father has a new car?