I think the main reason is that there are no equations that involve the third derivative explicitly.

我想主要原因是因为还没有等式,明显涉及三阶导数

耶鲁公开课 - 基础物理课程节选

The main reason why I say that is actually not necessarily because of what's in the museum, but because of the museum itself.

我这样说，并不一定是因为博物馆里的东西，而主要是因为这个博物馆本身。

喜欢的艺术家 - SpeakingMax英语口语达人

It doesn't work that way for a variety of reasons, but the main reason is that you want some decisions to be made at each space between two cells.

这出于很多原因,但主要的原因是,在每个细胞间隙,都需要决定信息是否继续传递

耶鲁公开课 - 生物医学工程探索课程节选

So that would suggest that education is probably not going to get the job done, because that's not the main driving reason because most people know that they shouldn't eat so much junk food, but education is what we default to when we think about what to do.

所以你们可能认为,教育并不能解决这个问题,因为这不是主要原因,大部分人都知道不该吃那么多垃圾食品,教育是思考解决方法时被忽略了的

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

which is the main reason I came here.

这是我来这儿的主要原因。

世界就是我的故乡 - SpeakingMax英语口语达人