I have a chart here, which I'll make available to, with a listing of nations with worse literacy record in the world.

现在我手中有一张表格，这个我会公开给大家，这里列出了世界上,具有较差文化素养的一些国家。

麻省理工公开课 - 媒体、教育、市场课程节选

You can make multiple--you can put three or four-- the copy gets worse and worse each time, but you've got multiple copies.

你也可以复写多份，放上三四张复写纸-,不过越往下复印的效果会越差，但终归你还是有了多份副本。

耶鲁公开课 - 金融市场课程节选

Because the difference in the vector between two times is this vector.

因为两个不同时间点上矢量的差,就是这个矢量 ΔR

耶鲁公开课 - 基础物理课程节选

I don't have the data in front of me, so let's emphasize the difference between r1 and rf.

我现在手头没有具体数据，我们现在把目光转移到r1和rf的数值差上。

耶鲁公开课 - 金融市场课程节选