So, literally earlier today when I was on my way to campus I emerged from the Harvard Subway Station and I was about to exit the station up the stairs when I noticed this older woman who was standing by one of these things.

今天早些时候，在我从哈佛地铁站,到学校的路上,我即将走出地铁站，上楼梯时,我注意到一个老太太站在,这样的东西旁边。

哈佛公开课 - 计算机科学课程节选

The very first thing I know is that it's a sign that says "exit."

我最先知道的是这是一个标志，上面写着存在“

耶鲁公开课 - 文学理论导论课程节选

And most of these commands you don't actually need but this little caret symbol means control, so every keyboard these days has a control key so you hold that and hit X for instance to exit the program.

这里大多数命令你们都用不着,这个小插入符意味着控制，每个键盘都有一个控制键,譬如，当你敲入X时，就退出这个程序。

哈佛公开课 - 计算机科学课程节选

It is in fact a very, very difficult and derivative act of the mind to try to forget that I am looking at a sign that says 'exit' and, in fact, just looking at what is there without knowing what it is.

事实上，试图忘记那个写着存在的标志,和只知道它存在而不知道它是什么，是非常难的事情。

耶鲁公开课 - 文学理论导论课程节选