and Mexican officials. Every day, thousands of people on foot and in vehicles go back and forth across the border here, and millions of dollars worth of products cross the line in trucks and railroad cars.

VOA: standard.2009.04.30

Once you know what pieces to look for, what mental constructs to reach for, can you realize all right I want to make some dancing figures go back and forth, I need to loop this way and loop this way and check if I'm on the edge and so forth.

一旦确定需要查找的部分,想要达到那种层次，你是否意识到,我想做出一些可以来回走动跳舞的人，我需要按这种方式那种方式让它转圈,并检查我是否,到了屏幕的边缘等等。

哈佛公开课 - 计算机科学课程节选

and then you go back and forth, back and forth.

于是你们两人你说一句，我说一句，争执不下。

I agree课堂 - SpeakingMax英语口语达人

It's reversible, that means that p external, equals p. I'm doing it very slowly so that I'm always in equilibrium between the external pressure and the internal pressure so I can go back and forth.

我都可以不损失能量，而把过程逆向进行,整个过程中的,每一步都保持平衡,现在我们来分别。

麻省理工公开课 - 热力学与动力学课程节选

John Now, you're going to hear John and I go back and forth a lot, well I'm certainly old time, but I'm also an old time Lisp programmer.

现在，你会听到我和,来回的讲好多次，好吧我当然是个老学究，但是我也是一个老lisp程序员。

麻省理工公开课 - 计算机科学及编程导论课程节选

So, let's listen to this bit of klezmer music go back and forth between minor and major.

让我们感受下这段犹太音乐,它在小调和大调之间转换

耶鲁公开课 - 聆听音乐课程节选

I go back and forth. Sometimes I agree with that.

我的看法摇摆不定。有时候我会同意这种看法。

介绍好朋友 - SpeakingMax英语口语达人

These memo-ons just go back and forth.

这些，memo-ons来回反复运动。

麻省理工公开课 - 固态化学导论课程节选

So energy can go back and forth.

所以能量可以来来往往。

麻省理工公开课 - 热力学与动力学课程节选

We can go back and forth between these two equilibrium states They're connected.

我们可以,在这两个平衡态间往返,它们是相互联系的。

麻省理工公开课 - 热力学与动力学课程节选