You always want to check your signs at the and because it's so easy to get the sign wrong, and I was hoping that it was right here because I wasn't sure, but it turned out to be right.

我们完成计算时，一定要记得检查符号,因为很容易弄错符号，刚才我就不太确定,是否弄错了符号，检查发现没有问题。

麻省理工公开课 - 热力学与动力学课程节选

Now if you look at my derivation here, there's one spot where I could have just stopped and proven my point without going through the whole thing.

如果仔细检查我的推导过程，你会发现其实,我们不用研究整个循环过程,就可以证明我们要证的公式。

麻省理工公开课 - 热力学与动力学课程节选

And so, he has put this chemistry to use in this robotic arm and they call it Fido, because often dogs are the creatures that have to go out and detect these things, and it's not a great job if you're a dog to be sent out to see whether there was an explosive and discover yes, there was, a little bit too late.

因为通常都是派狗去检查这些东西,这个不是个好工作，如果你是一只狗,被派去检查是否有爆炸物，然后你发现有,那就来不及了,所以用机器手检查化学物质。

麻省理工公开课 - 化学原理课程节选