And in fact, one of the lessons you may already be realizing with P sets is that things seem to take twice, three times, four times longer than you actually might think.

从习题集中你可能已经得出的一个教训就是,程序所花的实际时间往往是你开始以为的两倍，三倍，四倍甚至更长。

哈佛公开课 - 计算机科学课程节选

Is that something that can go for a semester or in the best of words for at least a year or more.

这种活动可以持续一个学期,乐观地说，至少可以一年甚至更长。

普林斯顿公开课 - 人性课程节选

Some things that actually wind up being really important take more than 10 years to get popular.

某些事需要10年，甚至更长时间,才会真正显现出重要性来。

斯坦福公开课 - 微软CEO-Steve.Ballmer谈科技的未来课程节选