Confederate General Robert E.Lee saw it as a sign of weakness in the northern war effort.

VOA: special.2009.11.05

If you want to get those e-mails, you got to sign up for the course because I push a button and it goes to anybody who's signed up there.

如果你想收到邮件的话,你得选我的课,因为我点一下按钮,邮件就发给选课的同学了

耶鲁公开课 - 基础物理课程节选