Generally speaking, closed schools are university campuses, especially during holidays, when there are too few students in the school, the remaining students are often unified in a dormitory, registered and issued access cards! Restrict outsiders from entering the school at will.
Universities have a history of thousands of years. At first, it mainly developed from Germany, Britain and other countries. Modern universities in China originated in the West, which evolved from European medieval universities, British universities, German universities and then American universities. No matter what era the university is, it is a creative inheritance rather than a denial of previous universities. The word "university" comes from the Latin Universitas Magistorum et scholium, which roughly means "the community of teachers and scholars". The modern university system has always been in the University of Eugen in the Middle Ages, which was established and evolved from the cathedral school in Italy in the Middle Ages.