I dare say you know about it already.

你大概已经知道了。

《牛津词典》

Don't let my son know about it.

别让我儿子知道这件事。

youdao

Few pupils know about it.

很少有学生知道这件事。

youdao

But he probably was the first to let the world know about it.

VOA: special.2009.10.27

All we really needed to know about it is that this is smaller right.

我们已经知道,这部分比较小。

麻省理工公开课 - 热力学与动力学课程节选

I don't know if there's anything in particular that you would like to know about it, but...

我不知道你有没有特别想了解的方面，但是……

在布莱恩公园 - SpeakingMax英语口语达人

In fact, how could any mind, if being honest with itself, not know about it?

BBC: Magazine

He was a great teammate, " and rookie Bradley Beal wrote: "I didn't know about it!

NPR: 'I'm Gay': NBA Player Jason Collins Breaks Barrier

But if nobody know about it, then all that effort has gone to waste.

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