I don't understand, though, why it's okay to take lots of one vitamin, but not another.

我不明白，可是为什么可以大量服用一种维生素，但却不能服用另一种呢？

youdao

I've heard about that. I don't understand, though, why it's okay to take lots of one vitamin, but not another.

我听说过。但是我仍然不明白为什么能大量吃一种维生素，但却不能吃另一种。

youdao

So you've got to understand when it's okay and when it's not okay.

你必须得知道,什么时候可以,什么时候不可以

耶鲁公开课 - 基础物理课程节选