Notice one last piece. If I'm going to do that, run through all possible answers, I still want to know, gee, what if there aren't any answers? How do I return that case?

注意最后一段，如果我要这样做，也就是运行所有可能的答案，我还是想知道要是没有结果呢？,在这个例子中应该返回什么呢？

麻省理工公开课 - 计算机科学及编程导论课程节选

Gee, have you ever wondered how they know the composition of stars that are light-years away?

嘿！你曾经是否想过,他们是怎么知道那些离我们好几光年远的,星星的位置的？

麻省理工公开课 - 固态化学导论课程节选

If I wanted to use print as a variable name, how do I get the system to decide gee, do I want print as a value for something, or do I want print as a command?

如果我把print当做一个变量名，我如何让系统来决定，我是要把print当做一个命令来用呢，还是要把它当做一个变量名来用呢？

麻省理工公开课 - 计算机科学及编程导论课程节选