Cooperate to correct errors. After each unit test, the teacher will comment on the test paper and analyze some common problems. However, due to the different types of students' wrong questions, it is impossible for the teacher to explain all the questions in one class. What can we do? We can let the students with good academic performance help the poor students, and the students with medium grades discuss with each other to correct the mistakes in the test paper. When commenting on the usual exercises after class, the teacher also asked the group leader to comment again after the teacher's comment. The group members did not understand the topic and made a correction check. In this way, it can create an atmosphere for students and teachers and students to study, explore and study problems together, and establish a dialogue and interactive teaching form.