But what we will find is, it's more convenient to lump these two numbers into a single entity, which is called a vector.

但我们会发现,将两个数值看作一个整体会更方便,我们称之为矢量

耶鲁公开课 - 基础物理课程节选

It's not necessary to do that, but it can be quite convenient.

虽然没有必要这样做，但是这样做是很方便的。

麻省理工公开课 - 热力学与动力学课程节选