What is the reason for not going to school during the epidemic?

Because of the strong spread, fast spread and close contact, even wearing a mask is inevitably infected. Take public transportation such as bus and subway on the way to school, which is crowded and easy to be infected. There are many students in the classroom, and if there are infected people, it is easy to produce cluster infection. Therefore, in view of the current severe epidemic situation, apply for home-based online classes.