The registrar will publish the schedule.

注册主任会公布时间表。

麻省理工公开课 - 固态化学导论课程节选

Once you have registered, if some other slots become available that weren't previously available, I gather you'll be sent some sort of email by the system, in case some other time would be better for you.

一旦你注册了，之前的有些项目,就可用了，系统会用邮件方式向你发送，让你的时间更方便。

耶鲁公开课 - 死亡课程节选