1, the ruler is 20cm long and 3cm wide. Ruler is a plank used by teachers in old private schools to punish students. It not only shows the prestige of teachers, but also creates the risk of students being hurt by corporal punishment. There are more and more discussions about whether rulers should enter the classroom.

2. Ruler, the wooden board used by Teacher Xue to punish students in the old days. Also called a ruler, it is made of two pieces of wood. The two trees incline upward and downward. The upturned person is seven inches and six minutes long, six minutes thick and one inch, and there are wisps of faces on the four sides below.