"We believe that South Africa has so much more economic potential and it cannot exist as an island of relative prosperity amid a sea of untapped opportunity elsewhere on the continent,"

VOA: standard.2009.08.08

And, believe it or not, I have students walk in and first thing a hand goes up and says do you have a pen? I cannot believe it.

不管信不信，我有些学生走进来，第一件事就举起手问,你有没有笔，难以置信。

麻省理工公开课 - 固态化学导论课程节选

People who hold constrained vision of human nature, believe that human nature cannot be changed; it's immutable-- we have certain instincts, we have certain inclinations.

认为人性受约束的观点的人，相信人性无法改变;,它是永恒的，我们有一些本能，有一些欲望。

哈佛公开课 - 幸福课课程节选