translation.en: I'm going to show you two movies, one from each of two conditions of an experiment, and because you're going to see just two movies, you're going to see just two babies, and any two babies differ from each other in innumerable ways.
translation.zh: 我将给你们放两段视频， 每一段各反映一个实验里的一种情况， 因为只有两段视频， 所以你们只能看到两个婴儿， 而任意两个婴儿之间都是千差万别的。