但是如果你的确是没有用它做任何事情，它只不过是看不见的，因此，它是-，做的好，第二号的同学。

But if you don't actually do anything with it, — it simply disappears, and, therefore, it's — well done, classmate Number Two.

youdao

知道和做之间有很大区别。知识是没有用的，如果没有行动的话。

There's a big difference between knowing and doing. Knowledge is useless without action.

youdao

那样做是没有用的。

It's no good doing that.

youdao

But if you don't actually do anything with it, -- it simply disappears, and, therefore, it's -- well done, classmate Number Two.

但是如果你的确是没有用它做任何事情，它只不过是看不见的，因此，它是-,做的好，第二号的同学。

哈佛公开课 - 计算机科学课程节选