We've talked about one the main concepts in physiology being homeostasis, that is 'how do you maintain a constant internal environment?

我们讲到了生理学的主要概念,内稳态,即如何维持内环境的稳定

耶鲁公开课 - 生物医学工程探索课程节选

In order for life to proceed, you need to maintain a constant internal environment.

为了维持生命,人体的内环境需要保持稳定

耶鲁公开课 - 生物医学工程探索课程节选

And sencondly to commit tens of thousands of troops to stabilise Afghnastan.

派出成千上万的军队来维持阿富汗的稳定。

普林斯顿公开课 - 国际座谈会课程节选