The proper way to draw a vector is to draw an arrow that's got a beginning and it's got an end.

画矢量的正确方法是,画一个有起点和终点的箭头

耶鲁公开课 - 基础物理课程节选

it's clear that you want to add a vector that looks like that, because then you go from the start of this to the finish of that, you end up at the same point and you get this invisible 0 vector.

显然应该给它加上这样一个矢量,因为从这个矢量的起点指向那个矢量的终点,最终指向的是同一个点,你就得到这个不可见的零矢量

耶鲁公开课 - 基础物理课程节选