As part of that study, 3,000 people in different countries, mostly college students, wrote about recent crying experiences.

VOA: special.2009.01.28

It is so important, in fact, we are going to study it in 3.091 in detail next month.

它很重要，事实上，我们将在下个月仔细地学它。

麻省理工公开课 - 固态化学导论课程节选