You don't see a red and yellow, you don't see green and blue.

你们不可能看到红连接黄 或者绿连接蓝

耶鲁公开课 - 生物医学工程探索课程节选

Now in a stoplight, it only has three, one is tempted to say, variables plainly differing from each other: red, yellow and green we have two ways of thinking about the red light.

交通灯，三种灯，红黄绿，它们的颜色和彼此不能,我们有两种方式认识红灯的意思。

耶鲁公开课 - 文学理论导论课程节选

One is that there's four different colors and so you can see red, blue, yellow, green here - four different colors and that's all there are, there aren't more than four.

一是这些梯阶有四种不同颜色,你可以看到红 蓝 黄 绿,恰恰只有四种不同颜色,不多不少

耶鲁公开课 - 生物医学工程探索课程节选