In many parts of the United States, cupcakes have become a popular replacement for cakes.

VOA: special.2009.09.11

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