It took a great deal of time and effort to gather fibers from plants or animals to make into yarn which could then be made into cloth.

VOA: special.2009.11.04

But we will also introduce towards the end of this semester in an effort to really make it okay to stay up all night, will be the first ever CS50 hack-a-thon.

但是，在这个学期末的时候,我们还会举办第一届CS50课程的Hackathon活动，你们可能还得熬夜才能完成它。

哈佛公开课 - 计算机科学课程节选