Each episode will focus on a different area of science and tell us what we know, how we know it, and what we still don't know.

每一集都将聚焦于一个不同的科学领域，告诉我们，我们知道什么，我们是如何知道的，以及我们仍然不知道什么。

youdao

It's a question rather of how we know the author to be there firstly, and secondly, whether or not we should appeal to the authority of an author.

首先我们如何知道作者在那儿，其次，我们是否应该诉诸作者的权威。

youdao

And you know how we know?

不过你知道我们怎么晓得的吗？

youdao

In her words, "We need to know how using credit fits into our plans and goals."

VOA: special.2009.05.22

So, we have beryllium in the first case here, it has four electrons, that's how we know it's beryllium, boron has five electrons.

那么我们将铍作为第一个例子，它有四个电子，这也是我们为什么能知道它是铍的原因，硼有五个电子。

麻省理工公开课 - 化学原理课程节选

Also, it is cylindrically symmetric around the bonding axis, so this is how we know that it's a sigma orbital.

此外，它关于键轴是圆柱对称的，这就是为什么我们知道它是sigma轨道。

麻省理工公开课 - 化学原理课程节选

The story of how we know all these facts is told through Mr. Scharf's personal experience.

WSJ: Book Review: Gravity's Engines

We talked about how we know that terrorists are focusing in on using airlines as some of their ways to commit terror.

WHITEHOUSE: Press Briefing

Mr Ferris is reminding us of how little we know about the world we live in, and how little we know about ourselves within it, and yet we persist.

ECONOMIST: New fiction 1