Does it give you the answer that you expected it to give? Often, in practical problems, you'll spend just as much time doing performance debugging. Why is it slow?

它返回了期待中的结果了么？通常,在实际的问题中你会花，同样多的时间在性能调试上,它为什么运行这么慢？

麻省理工公开课 - 计算机科学及编程导论课程节选

Can you explain to us about stem cell research and why it's so controversial?

你能跟我们解释一下干细胞研究，
以及为什么这项研究会受到这么多的争议吗？

干细胞和伦理 - SpeakingMax英语口语达人

That is why you paid so much money to come here.

那就是你们为什么要花这么多钱来这的原因。

麻省理工公开课 - 固态化学导论课程节选

Does anybody know why so much time is spent on that? Yes?

有谁知道为什么要在这上面花这么多时间吗,你说

耶鲁公开课 - 基础物理课程节选