If you visit the western mountain and plains state of Montana you will know why it is known as Big Sky Country.

VOA: special.2009.08.16

It's crucial to you to know exactly what it means and why what it means is important.

对你来说，知道它的确切的意义，以及解读它的重要性,都是十分关键的。

耶鲁公开课 - 文学理论导论课程节选

To gain an understanding of some of the issues involved, and the emergence of a tribal structure in the land, it's helpful to know something about the geography of Israel, which is why I have handed out for you a couple of different maps but one that gives you physical features .

为了了解其中一些事件，以及在这片土地上逐渐出现的部落形式，了解以色列的地理是很有好处的，这也就是我给你发了几份不同地图的原因,其中有一幅呈现了物理特点，在最上面。

耶鲁公开课 - 旧约导论课程节选

The ones I'm talking about all have to do with the Peloponnesian War which is one of the reasons why we know a little bit about it, because Thucydides tells us the details of it.

我所说的事都与伯罗奔尼萨战争有关,这也是为何我们对它的了解要多一些,因为修昔底德告诉了我们一些细节

耶鲁公开课 - 古希腊历史简介课程节选

This is very important,which is why I am doing it: "If we want to know how fast a human being can run, then it is no use to average out the speed of a "good sample" of the population; it is far better to collect Olympic gold medal winners and see how well they can do.

这话非常重要，是我作这个研究的原因：,“如果想知道人类最快能跑多快，那从好的样本中测出平均数是“,没用的;,而应该收集田径类奥运冠军的信息,看他们能跑多快。

哈佛公开课 - 幸福课课程节选

It's a secret number so that if Julius Caesar scrambled his message with the key 13, well, then the recipient had better know what that number is or realistically, -- and this is why it's kind of hard to buy -- into some of these age old algorithms, -- what would an alternative approach be to figuring out Julius Caesar's messages to his generals if he didn't know that secret number was 13?

它是一个机密的数字，以至于,如果凯撒大帝使用密钥13加密了它的消息，然后接收者最好知道那个数字是什么,实际上--这就是为什么很难,破解这些古老的算法-,有什么变换方法使凯撒大帝的将军,可以解密凯撒大帝的消息，如果他不知道,那个机密数字是13呢？

哈佛公开课 - 计算机科学课程节选