Read the【Case Reflection】in this section and think about the questions:

Mr L firmly believes that “Being lax in teaching is the sign of a lazy teacher.” So he is very strict with his students. This semester he took over a class that was famous for bad behavior. Four students were late for his first class. He asked the monitor to take down their names, and summoned them to the office after school and reprimanded them. The four students have been hostile to him ever since. They played little tricks or simply slept in his classes. After a semester, Mr L feels tired and the four students' results have worsened markedly. Can you give Mr L some suggestions?

After a semester, Mr L feels tired and the four students' results have worsened markedly. Can you give Mr L some suggestions?