How can we prevent murderous schoolyard violence in children who have access to weapons,poor parental supervision, and a mean streak?"

如何防止校园暴力,这些暴力事件通常是由掌握武器，缺乏父母监管，或受到教唆的孩子引起的“

哈佛公开课 - 幸福课课程节选

Nobody knows how bad the mortgage crisis is going to get but Ben Bernanke thinks that it's so important that we prevent a collapse that we should take that risk.

没有人知道抵押危机,到底会有多坏的影响，但是本？伯南克认为,预防承担那个风险所带来的暴跌,是非常重要的。

耶鲁公开课 - 金融市场课程节选