Wood and coal for fuel. Technology solved many of the problems.

VOA: special.2010.04.15

The problems that Frost's poetry poses for us as readers are not problems of reference. They can't be solved by footnotes.

他的诗歌给我们的困难,不是参考的问题，它们不能就用脚注解决。

耶鲁公开课 - 现代诗歌课程节选

If I haven't solved the problem, let me solve it, and store the answer away for later reference.

让我解决它，然后保留答案以备下次调用。

麻省理工公开课 - 计算机科学及编程导论课程节选

other people had solved that problem for me, and this thing between quotes, we'll start calling a string.

至于如何实现的别人已经解决了，这个在引号之间的东西叫字符串。

哈佛公开课 - 计算机科学课程节选

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