I don't know how this happened.

我不知道这事怎么发生的。

《牛津词典》

You know how prickly she is.

你知道她多么容易生气。

《柯林斯英汉双解大词典》

We don't know how the transcript leaked.

我们不知道抄本是怎样泄露的。

《柯林斯英汉双解大词典》

He said he would get it, but first he wanted to know how big she thought the moon was.

VOA: special.2009.03.28

So we can go ahead and name our molecular orbital, just like we know how to name our atomic orbitals.

我们可以继续命名分子轨道，就想我们知道如何命名原子轨道一样。

麻省理工公开课 - 化学原理课程节选

And once you know how it sounds, making those sounds for yourself would be a lot easier to do.

一旦你知道该怎么发音，你就能更加容易地把它说出来。

想征服英语的话 - SpeakingMax英语口语达人

"I was ashamed, too shy to tell him I didn't know how to pray, " Leuco wrote.

CNN: The 'cold call' Pope rings again

There is little question that people living in America should know how to speak English.

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Let me know how you are feeling and doing as you find more positive four letter words.

FORBES: Briefing Book: A. Michael Lipper