So you're implementing this black box, and if its purpose in life is to actually return a value, you have to tell the compiler what kind of value to expect, and this is going to have ripple effects.

你在实现这个黑盒子，如果它的目的是,返回一个值，你必须告诉编译器你期望的是什么类型的值，这个将是一个连锁反应。

哈佛公开课 - 计算机科学课程节选

The prototype is just its return value, its name, and its arguments, if any.

原型就是他的返回值，它的名字，它的参数之类的。

哈佛公开课 - 计算机科学课程节选

The only thing that you have to put in the function prototype, ; again, is three things; one, the name of the function; the return value; and its arguments.

你唯一要加入到函数原型中的东西，是有三个东西，一，函数的名字;,返回值，和它的参数。

哈佛公开课 - 计算机科学课程节选

It's defined in CS50's library; its sole purpose in life is to ask the user for a floating point value and return it.

它被定义在CS50的函数库中，它的唯一目的是,向用户询问一个浮点数的值，然后返回它。

哈佛公开课 - 计算机科学课程节选