The Tennessee senator also wants more exploration for offshore oil and natural gas, and more conservation and efficiency in electricity use.

VOA: standard.2009.04.25

OK. So to do this, we need a little more abstract way of talking about efficiency, and so, the question is, how do we think about efficiency? Typically there's two things we want to measure.

好，为了达到这个目的,我们需要用一种有点，抽象的方式去讨论效率，这衍生出来,一个问题，我们该怎么去认识效率？,主要来说我们有两个要量化的东西。

麻省理工公开课 - 计算机科学及编程导论课程节选

If the vehicle in the unfortunate circumstances of a collision, has to be able to maintain the security of the hydrogen which means more mass, which means a lot of the efficiency is being squandered What's the environmental impact of hydrogen production?

如果车辆,在碰撞中发生了不幸，要仍然能够保持氢气的安全性的话,意味着需要更多的质量，也就是说大部分效率被浪费了,制氢对环境有什么影响呢？

麻省理工公开课 - 固态化学导论课程节选