It's just a placeholder that says I don't yet know what I wanna put here but I wanna put something, let me get back to you in just a moment.

它只是一个占位符，告诉电脑,我想在这放一个东西，但是暂时还不知道放什么东西，我先打断一下。

哈佛公开课 - 计算机科学课程节选

Put some money in and then you think about it and then you call me up and say, do you want to buy some stocks.

存入一些现金,想一想,再告诉我,要不要买些股票

耶鲁公开课 - 金融市场课程节选

There's even eating meditation, you did it once with me, and I've done this in other places where you take a raisin and you put it into your mouth, and you take a minute to eat this raisin.

甚至还有食禅，我们一起试过一次，我也在别的地方试过,你拿着一粒葡萄干,放入嘴中，花一分钟时间吃掉这粒葡萄干。

普林斯顿公开课 - 人性课程节选

So, summarizing better, assert is something you put in to say to the user, make sure you're giving me input of this type, but I'm going to guarantee you the rest of the code works correctly. Exceptions and exception handlers are saying, here are the odd cases that I might see and here's what I'd like to do in those cases in order to try and be able to deal with them.

所以更好的总结下,断言就是你放在那里告诉用户,保证你输入的是这种类型的,但我能保证剩下的代码运行正确,异常和异常处理做的事,这里有些我能预期的异常情况,并且这里有些情况,我能尝试处理。

麻省理工公开课 - 计算机科学及编程导论课程节选