"We say,find more American energy and use less--energy that is as clean as possible, as reliable as possible, and at as low a cost as possible.

VOA: standard.2009.04.25

As we expected, it's less than one, and of course if we build an engine, we want it to be as high as possible, as close to one as possible.

就像预先期待的一样，效率小于一，当然如果我们建造一台热机，我们希望效率越高越好，尽可能接近一。

麻省理工公开课 - 热力学与动力学课程节选