Maybe it won't now that we have better plans to prevent things like that, but suppose it did happen.

也许现在不会，我们有更好的方案,阻止这种事情发生，假设它真的发生了。

耶鲁公开课 - 金融市场课程节选

They merely were there in a time of emergency to prevent hopefully a banking crisis.

它们只是在危急时刻,阻止一个银行业危机的发生。

耶鲁公开课 - 金融市场课程节选