What I know for sure is that what you give comes back to you.

我非常确信一点，就是你付出过什么，你就会有什么回报。

youdao

But what I know for sure is that when I stop playing I want a complete break.

但现在能确定的是当我退役时，我想得到一次完完全全的休息。

youdao

This is what I know for sure: in order to be truly happy, you must live along with and you have to stand for something larger than yourself.

我可以非常肯定的是为了追求真正的快乐，你必须为了一些更有意义的事而生活。

youdao

What I know for sure is that Social Security is the backbone of our country.

FORBES: Will Social Security be there for You?

But here's what I know for sure: Since the day he took office, Barack has been fighting for us.

WHITEHOUSE: Remarks by the First Lady at a Campaign Event -- Seattle, WA

But what I know for sure, what I can tell you that your President is doing since the day he took office, Barack has been fighting for us.

WHITEHOUSE: Remarks by the First Lady at a Campaign Event