Same way that I have multiplication or division as a primitive, functions are going to give me, or somebody else who wrote them for me as part of a library, a new primitive that I'm going to be able to use.

我在用乘法或者除法当做原语,这些函数,或者别人写程序库中的函数,将会给我返回一个,我能使用的新原语。

麻省理工公开课 - 计算机科学及编程导论课程节选

But long story short, if I want to use a function called sleep, -- the reason I, the programmer, knew to use that library -- -- that header at the top -- because it told me to in this little synopsis.

但长话短说，如果我想要用一个叫做sleep的功能，我作为程序员知道使用那个函数库-,上面的标题-,因为在这个小的大纲中它告诉我。

哈佛公开课 - 计算机科学课程节选