I don't know. Correction—I do know, but I'm not going to tell you.

我不知道。不，我知道不假，但不打算告诉你。

《牛津词典》

We do not even know, for example, how many stars have planets, and we certainly do not know how likely it is that life will arise naturally, given the right conditions.

例如，我们甚至不知道有多少恒星有行星，我们当然也不知道如果有适当的条件，生命自然出现的可能性有多大。

youdao

The question of what we know and do not know constantly bothered me.

我们知道什么和不知道什么这个问题一直困扰着我。

youdao

"Aylmer," said Georgiana, "I do not know what the cost would be to both of us to remove this birthmark.

VOA: special.2009.09.26

We need to know not only what are the primitives, but how do we make things meaningful in that language.

我们不仅需要知道什么是基本类型，还要知道我们在那种语言中,怎样使其变得有意义。

麻省理工公开课 - 计算机科学及编程导论课程节选

But, you know why not do something a little special, little different, and they decided instead to use lithium.

但是你懂的，为什么不做的更特殊，更与众不同一些呢？

麻省理工公开课 - 化学原理课程节选

We do not know, still do not know, what are all the feedbacks in the system.

FORBES: Global Warming Will Increase Tropical Forests

We really do not know how much is down there, we do not know which portion of whatever is down there is retrievable and we do not know the cost of doing so.

FORBES: UK Government Being Fools About Shale Gas

But at this point, I do not know what that is. do not know whether spiked pensions can be reeled back in.

FORBES: Muni Bankruptcies Set Up War Between Pensioners And Bondholders