And I think many parents believe that if they didn't persist in using these things their children would never learn to speak.

我相信很多父母认为,如果他们不坚持使用这些东西,他们的孩子将永远也学不会说话

耶鲁公开课 - 心理学导论课程节选

I recommend it, but only credit/D/fail.

我推荐这门课，但必须坚持出勤/D/不及格。

耶鲁公开课 - 死亡课程节选