英语翻译"你知道吗?" "我不知道你说什么"

你知道吗？
You know what I mean?
Do you get it?
我不知道你说什么。
I don't follow you.
I don't know what you were talking about.
I don't get it.

get it表示知道、理解的意思，是口语比较常用的说法，相对更地道一些

你知道吗？（Do you know?）
我不知道你说什么。（I do not know what you said.）

"你知道吗?"
Have you got it?
Can you understand me?
"我不知道你说什么"
I don't know what you said.
I don't understand what you said.

you know?
i can't catch you