This is called the mirror wall. It is an indispensable facility for dance teaching. The main function is that students can see their own movements, movements from different angles, movements of classmates, compare their own movements, and see their position and position in the collective queue. Teachers can see students' movements in any position in the classroom more comprehensively, and can view a person's movement state from two angles: real scene and mirror image. So this mirror wall device is very important.