Say, we're just doing this once and don't expect it again.

就说,我们只分一次红,别想有下次

耶鲁公开课 - 金融市场课程节选

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