"我不知道你在说什么"用英语怎么说？

I don't understand what you are saying.
I don't know you're talking about.
I don't cotton on to what you are saying.
我不明白你在说什么。

i don't know what are you taking about?追问

不是" I don't know what you are talking about "吗？

追答

你是正确的

I don’t understand what you said.

i don't know what you are saying