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

Whether you take the elevator to the top of the Hancock Tower or whether you walk up the stairs, the change in gravitational potential is identical.

不管你是乘电梯,去大厦的顶层,或者是步行，重力势能的变化是相同的。

麻省理工公开课 - 固态化学导论课程节选

You need to walk down the stairs and then up the stairs.

要被迫上下楼。

哈佛公开课 - 幸福课课程节选