It's really my fault to do math homework in class. First of all, as a student, I should finish the homework assigned by the teacher within the specified time. Secondly, I shouldn't write other homework in other teachers' classes, which is not only disrespectful to teachers, but also disrespectful to subjects. As a result, I didn't master the knowledge of two courses, which also made the teacher very angry. So I wrote this critical letter today, which is not only a negative teaching material for other students, but also a warning and review for myself. I'm sorry, teacher. Today, I will review, make sure to finish my homework on time and listen carefully in class (thank you, if you want to watch it). Finally, I will write: name and date.