If you look at the normal labs that are in many places, you have a lab on Thursday afternoons, and the labs are either two weeks ahead or two weeks behind the lecture material.

如果你了解其他地方,一般的实验室，比如在星期四下午有实验课，这些实验要么是讲座的两周前,要么是讲座的两周后,才进行。

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