We have no detentions or such things at my school... If you begin to annoy your professor, you get a 1(grades from 1 to 5 with 1 being worst) so everybody tries not to be annoying. But professors aren't strict at all, you can make jokes or talk in class and they won't punish you unless you really mess up.

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Sometimes stop, look back.
They're haunting you, pure black.
Relinquished dreams, fallen leaves,
freezing wind, memories.