They truly got into the spirit. And in the second party one of the students took the microphone and she got everyone to start singing Christmas songs, which to me helped bring up the whole spirit of why we were there."

VOA: standard.2009.12.24

One is there's no lag period, notice that antibody levels start rising right away after the second exposure.

第一是没有迟滞期,请注意,抗体浓度迅速上升,在第二次接触抗原时

耶鲁公开课 - 生物医学工程探索课程节选

It turns out that if you start learning a language, a second language is where most of the work's been done, within the first few years of life you're fine.

如果你在出生的头几年里开始学习一门语言,非常努力地学习了第二门语言,那么你一切正常

耶鲁公开课 - 心理学导论课程节选