如果我站在这里，你们不移动，我移动这些音叉，那么你们会听到不同，频率，这就是我们，所说的多普勒效应。

If you stay where you are and you don't move and I move these tuning forks, you will hear a different frequency and that's what we call Doppler effect.

youdao

这也是前面几个问题中所提到的，为什么我来这里能够帮助美国人民就业、购买住房、培养孩子上大学、实现我们所说的美国梦。

That accounts for some of the questions here, about how concretely does me being here help them find a job, pay for their home, send their kids to college, live what we call the American Dream.

youdao

我在这里所说的平等是相对平等，因为事物本身的差异性，男女之间的性别关系，无论如何我们总是不能做到绝对平等。

I'm here to say equality is relatively equal, because the difference of the thing itself, the gender relations between men and women, no matter how we always can't achieve the absolute equality.

youdao

So I show that here, so in green, you have what's called a carboxcylic acid group, a c o o h, which gets converted by s o c l 2 to a c double bond o c l or an acid chloride.

我在这里用绿色表示，我们所说的羧酸族化合物，碳，氧，氧，氢，它被亚硫酰氯转化为,一个碳氧双键与碳氯单键组成的酰氯。

麻省理工公开课 - 化学原理课程节选