So, the question becomes, well, what are the resources for magnesium?

所以问题就变成了，镁资源从哪里来呢？

麻省理工公开课 - 固态化学导论课程节选

You could use a "who" question to find out where the problem began.

你可以用“who”问句来找出问题从哪里开始。

Who 课堂 - SpeakingMax英语口语达人

So that were clear from the outset: where we are coming from,where I am coming from, and also so that we can build the foundation of the course.

下面这些问题非常明确：,我们从哪里来，我从哪里来，了解这些后我们就能建立本课程的基础。

哈佛公开课 - 幸福课课程节选