What I am going to do next day is go into the larger stoichiometry and understand the principles of mass balance and reactivity But before you go,hold it,I don't want you racing off.

下堂课我要做的是,讨论化学计量学，和,质量平衡很反应定律,但在下课之前，我不希望你们这么快走。

麻省理工公开课 - 固态化学导论课程节选

Isn't it difficult being a mother and a professor at the same time and keeping a balance between the two?

同时做母亲和教授是不是很困难呢？两者之间取得平衡不容易吧？

教授的梦想 - SpeakingMax英语口语达人