直到几个月后，他才知道这故事。
It was not until a few months later that he knew the story.

我怎么知道。
How should I know.

我知道那种感觉。
I know the feeling.

幸好知道了这件事。
That's good to know.

你知道他欺骗他的妻子吗？
Did you know he was cheating on his wife?

我知道如果我坚持下去就会成功。
I knew if I kept at it I should succeed.

我知道发生了什么事。
I know what happened.

你知道这道题的答案吗？
Do you know the key to the problem?