But earlier,Buzz Aldrin the second man to walk on the moon took part in a NASA news conference where he pushed for a new round of space exploration, with the goal of sending astronauts to Mars.

VOA: standard.2009.07.20

Second, he looked at these people and measured how fast they walk from where their experiment was to the elevator.

第二，他观察这些人,记录他们从实验地点,走到电梯的时间。

哈佛公开课 - 幸福课课程节选

I'm given an integer that's a perfect square, and I want to write a little piece of code that's going to find the square root of it. All right so I'm cheating a little, I know it's a perfect square, somebody's given it to me, we'll come back in a second to generalizing it, so what would the steps be that I'd use to walk through it?

完美平方数的整数，我想写一段代码来求这个数的平方根,好，我这儿有点儿作弊了,我知道这是一个完美的平方数了,他们给我的，我们后面会讲怎么产生这个数的，那么我想解决这个问题,需要什么步骤呢？

麻省理工公开课 - 计算机科学及编程导论课程节选