A teacher, no matter how good, has to give this one-size-fits-all lecture to 30 students -- blank faces, slightly antagonistic -- and now it's a human experience, now they're actually interacting with each other.
一个不论多么优秀的教师， 都不得不按同一个步调 给30个学生讲课。 面无表情的脸庞，小小的 而现在是人性化的经历。 现在他们可以互相合作来完成作业。