你怎么知道那件事？

Why do you know that?

youdao

你怎么知道那件事的？

How did you know that?

youdao

你是怎么知道那件事的？

How should you know that?

youdao

那么你是怎么知道那件事的呢？'他插嘴问道。

But how do you know that? 'he interposed.

youdao

那么你是怎么知道那件事的呢？'他插嘴问道。

But how do you know that? 'he interposed.

youdao