Nowadays, if you go to outer space, you can check for yourself that if you throw something out, it just goes on forever without your intervention.

现如今,如果你去了外太空,你可以向外抛个物体试试,如果你不打断它,它就会一直运动下去

耶鲁公开课 - 基础物理课程节选

So unlike Scratch where you pretty much had to say "repeat" ten times or whatever, or forever where it's just "forever" with for loops, -- can you actually specify a finite number of iterations -- and as I learned 15 years ago, finite is important.

所以不像Scratch，你大致上需要用,“repeat“10次或更多，或者需要不断地使用当它,是死循环时，你们能够指定出一个有限的迭代次数-,像我15年前学的，有穷的是重要的。

哈佛公开课 - 计算机科学课程节选