There have been fundamental changes through time that make the role of the central bank evolve and change through time.

试图保持系统的稳定,随着时间的发展，基本的改变发生,使得中央银行的角色演变。

耶鲁公开课 - 金融市场课程节选

You get an economy subject to convulsions during that period.

我们的经济,在那段时间极不稳定。

斯坦福公开课 - 经济学课程节选