" ...when all of God's children, black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual: Free at last! Free at last!

VOA: special.2010.04.16

So, I encourage you to do that the next time you have some free time on your hands, maybe at IAP or some time like that.

下次你有空余时间时,我鼓励你去看一看，也许在IAP或者什么时候。

麻省理工公开课 - 化学原理课程节选

So, I encourage you to do that the next time you have some free time on your hands, maybe at IAP or some time like that.

下次你有空余时间时,我鼓励你去看一看，也许在IAP或者什么时候。

麻省理工公开课 - 化学原理课程节选