And these verbal descriptions lead to some pictures that I put up and I'll put up again about how you might try to accomplish something like run an engine or move heat from a colder to a warmer body.

这些言语的描述有助于你们理解我讲过的,而且还要再讲的一些物理图像,比如一台发动机,是怎么运行的,或热怎样从冷的物体传到热的物体。

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In that process there is a metabolic engine at work, and some people have an efficient engine so that the calories in get banked in the fat, other people have an inefficient engine, that is the calories get wasted as body heat and things like that, and they tend not to gain weight.

这过程中人体内有个工作着的代谢引擎,有些人的代谢引擎效率很高,热量便转化为脂肪储存起来,另一些人的效率低下,能量就以体温等形式被浪费了,因此他们就不容易发胖

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