计算机起着文字处理器的作用，一篇讲话的文本可随时输入。

The computer acts as a word processor where the text of a speech can be input at any time.

《柯林斯英汉双解大词典》

这个作业的作用是计算单词在输入文件中出现的次数。

Recall that the point of the job is to calculate the number of times words occurred in the input files.

youdao

这里的原理是 lookup 的源输入被作用一个键。

The idea is that the source input of the lookup is used as a key.

youdao

Something that takes two inputs, a left operant - and a right operant and it just returns a Boolean value is-- or rather it returns a left to right value.

它有两个输入，一个是左边的作用物,一个是右边的作用物，然后返回一个布尔值-,或者更确切地说，返回一个从左到右的值。

哈佛公开课 - 计算机科学课程节选