Now, your temptation is to keep the first answer because you know energy is not going to be negative.

你肯定想保留正根,因为你知道能量不会是负值

耶鲁公开课 - 基础物理课程节选

Unless, of course, you're a smoker, or you're thinking of becoming a smoker, and then maybe you should worry, because this is one of the advertisements that was airing in terms of anti-smoking campaign.

除非，当然，你吸烟的话，或者你正考虑开始吸烟，那么你可能就需要担心了，因为这是反吸烟运动的,宣传内容之一。

麻省理工公开课 - 化学原理课程节选

So you're not going to forget this particular melody and it's because it sounds so grand.

因此你不会忘记这个旋律,而且正因为它听起来如此恢宏

耶鲁公开课 - 聆听音乐课程节选

I'm really liberal, but this disturbs me because I am looking at you, I'm trying to see from your reaction how much of my lecture you are following, and then it's very distracting when people are talking.

很无所谓的,但是我很不喜欢有人说话,因为我正看着你,我要根据你的反应来判断,我的课你听懂了多少,但是如果有人说话的话,就会让大家分神

耶鲁公开课 - 基础物理课程节选

So you don't want to put in a negative energy, that's not going to help you out, you need to put in positive energy to get an electron out of the system. So that's why you'll find binding energies are always negative, and ionization energies are always going to be positive, or you could look at the equation and see it from there as well.

因为这对电离没有帮助,你需要一个正的能量,使得电子脱离这个系统,这就是为什么你会发现,结合能总是负的而电离能总是正的,或者你们看这个方程也可以发现这一点。

麻省理工公开课 - 化学原理课程节选