If you wish to change sections, you may do so only with permission of the subject administrators because it's very important that those sections be kept at a small population.

如果你们想要改时间，你只能在课程管理主任允许,的情况下这样做,因为让课程的人数保持在比较少的水平,是很重要的。

麻省理工公开课 - 固态化学导论课程节选

I only had one year left of university, it was too late to, to change from... to a too different subject,

我还有一年就要毕业，所以已经来不及换专业了，

换专业的理由 - SpeakingMax英语口语达人