So some people began to be clever, either putting a book or a water cup to show that this is someone's seat, and some people are even lazier. They wrote a note, covered it with a pen, and said that they had gone to the toilet and would be right back. The result was an afternoon.
Although it is easy to occupy a seat, it is disgusting. Some people who are not interested may just throw away your things.
Whispering in review and study, it is inevitable that some students especially like learning and have no bad habits, but when they get to the back, they recite it silently in the study room, fearing to disturb others, thinking that they are quiet, but others hear it buzzing, just like chanting.