So that's where it's easy to get lost, but let's see if these lines in the picture help us stay on track.

这就是容易迷惑的地方，下面看看,这幅图中的这些线能否帮助我们追踪。

哈佛公开课 - 计算机科学课程节选

Well there are methods that get used to track population intake and methods to track individual food intake, and let's talk about each of them.

有的方法,用于追踪总体摄入量,有的方法追踪个体食物摄入量,让我们分开来谈

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选