translation.en: We challenged ourselves to create an online class that would be equal or better in quality to our Stanford class, but to bring it to anyone in the world for free.
translation.zh: 我们挑战自我 决心去创建一个在线网上课程 这门课程将会和我们在 斯坦福的课程质量媲美甚至更好 而且还能给来自世界各地的人们 免费学习的机会