So biomedical engineers have been working for many years on how to design replacement parts for joints like the hip: the artificial hip is the most well developed of those.

因此,生物医学工程师花了很多年时间,致力于设计像髋关节这样的关节替代品,尤以人工髋关节的研究最为成熟

耶鲁公开课 - 生物医学工程探索课程节选

I want to end this premise idea by talking a little bit about a person for whom, one of the chief purpose in life was to spread happiness-- Mahatma Gandhi. This is a story about him.

我想以介绍一位,一生致力于，传播快乐的人来结论这个前提-,圣雄甘地，这是关于他的一个故事。

哈佛公开课 - 幸福课课程节选