In bridge building we're well advanced in understanding what are the problems with building bridges and how do we overcome them?

在桥梁建设中我们十分清楚地了解,在造桥的过程中会遇到什么问题,以及如何克服这些问题

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There's always construction.

总有很多在建设中，

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And that makes it for me a very exciting time to study this because the problems aren't solved in the way that bridge building is largely a solved problem now.

对于我而言,这是一个非常激动人心的时代,因为一百年前桥梁建设中难以解决的问题,在今天都得到了解决

耶鲁公开课 - 生物医学工程探索课程节选