There's a lot of fluctuations in exchange rates over time.

随着时间的推移，汇率会不停地上下波动。

斯坦福公开课 - 经济学课程节选

I want to talk first about institutions and then move to what I think is, myself, more interesting, which is the real estate boom and the kind of fluctuations we've seen in real estate over the years.

我首先会讲讲这些机构,然后讲一下我更感兴趣的,房地产市场繁荣,及这些年里,我们经历的波动

耶鲁公开课 - 金融市场课程节选

There can be a supply of them, a storehouse of them that can build up in the body, and so day-to-day fluctuations become less of a problem with fat soluble then water soluble vitamins, because the body can go grab them from a storage depot, if you will.

从而在体内建立起一个供应源,一个脂溶性维生素仓库,这样一来,相比起水溶性维生素,脂溶性维生素的浓度不会每天剧烈波动,因为机体可以任意取用体内的储存

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选