Again, I don't have data to back this up, but just common sense suggests to me that the common case is if I'm on the subway platform I want to get on that train and maybe I want to get back and where are those two buttons, right?

此外，我没有数据来备份这个，但是常识告诉我，常见的情况是,如果我站在地铁站台上，我想乘上地铁,可能我还想回来,那么哪里能找到这两个按钮，对不？

哈佛公开课 - 计算机科学课程节选

And, at the very beginning there was a train that went around the Wall of Paris, more about the walls of Paris another time, that's fun to talk about, and Parisians would take picnic lunches, and they'd get on the train, and then they'd hear these large explosions and realize that they could get killed by these large explosions.

一开始的时候,有一趟火车,是绕着巴黎城墙行驶的,下次我们多讲讲巴黎的城墙,这挺值得一谈,巴黎人会带着午餐便当,坐上火车,然后他们听见了巨大的爆炸声,突然意识到他们可能会被炸死

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