当我们沿着一条拥挤的街道向前走的时候，我们听到后面有急促的脚步声和喊叫声。

And then, walking down a crowded street, we heard behind us the sound of pounding feet and somebody yelling at us.

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那么当我们沿着行向右走的时候，这是我漂亮的元素周期表。

So as we go across the row, and this is my beautiful picture of a periodic table here.

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但是，当我们到达山脚下的时候，我爱人劝说我女儿跟她一块去绕着山路走一圈。

But when we reached the foot of the park, my wife persuaded my daughter to take a circling walk around the mountain with her.

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As we go down a column, what happens is that the ionization energy decreases.

当我们沿着列向下走的时候，会发现电离能是在降低的。

麻省理工公开课 - 化学原理课程节选

So, as we go down a column, we see ionization energy's going to decrease.

总之，当我们沿着列往下走的时候，我们会看到电离能在降低。

麻省理工公开课 - 化学原理课程节选

I just doubled the indentation each time so you can see it. So each successive call, notice what's happening. The argument is getting reduced. And we're going another level in. When we get down to this point, we're calling it with just a string of length one.

因此每次成功调用注意它的过程,我们的命题不断简化，而且我们不断深入嵌套,当我们走到这一步的时候,我们就是在调用它处理，仅有一个元素的字符串了。

麻省理工公开课 - 计算机科学及编程导论课程节选