So, if magnesium is so abundant, why is it so expensive?

所以如果镁是如此富饶，为什么它这么贵呢？

麻省理工公开课 - 固态化学导论课程节选

It's expensive to live in New York, so a lot of people are wealthy, but not everybody is. I'm not.

在纽约安家是非常昂贵的，因此一定有许多有钱人，但不是每个人都是有钱人。我就不是。

上西区的人们 - SpeakingMax英语口语达人

Well because you can, because it's less expensive to do so than it is elsewhere in the world and people naturally like sweet tastes.

一是因为你能做到,二是因为这么做的成本比在其他国家低,更何况人们天生喜欢甜味

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Why is it so expensive?

为什么它这么贵呢？

麻省理工公开课 - 固态化学导论课程节选

Oftentimes, inventions that seem, in the abstract, to be good ideas may be impossible because something that you have to do to make it actually come into practice is too expensive and so it's not economic to produce the invention.

通常在理论上,创新固然不错,但却很难实现,因为把创意变成现实,花费会相当的昂贵,实现这样的创意非常不合算

耶鲁公开课 - 金融市场课程节选

And so, Columbia helps us pay our housing so, because it is very expensive to live up here.

而哥伦比亚大学帮助我们付了房租，因为在这儿住实在太贵了。

上西区的人们 - SpeakingMax英语口语达人