Even though the recession has forced a drop in the amount it costs to buy commercials in the big game for just the second time in history, they are still the most expensive on television.

VOA: standard.2010.01.27

I don't know where that is, that disappeared on the blackboard, then putting the time equal to 1 second into this formula.

我不知道我写在哪儿了,已经不在黑板上了,然后把时间等于1秒代入方程

耶鲁公开课 - 基础物理课程节选

Now, why is the time less on second exposure?

为什么再次免疫花费的时间少呢?

耶鲁公开课 - 生物医学工程探索课程节选

You don't mind watch it a second time Actually I watched it many times, on DVD in particular. Did you use the DVD?

你们不介意再看第二遍吧,事实上我看了很多遍，特别是看DVD，你们看DVD吗？

麻省理工公开课 - 电影哲学课程节选