At present, primary school teachers are basically bachelor degree or above, have teacher qualification certificates, and have also learned relevant pedagogy knowledge in undergraduate courses. Primary school mathematics and English are relatively simple, so art teachers teach mathematics and physical education teachers teach English, which should be fully competent in primary schools.
I am most afraid that art teachers and physical education teachers have their own schedules. When there is a conflict in class time, this teacher takes over once and that teacher takes over once. If the sense of responsibility is not strong, the quality of teaching will not be guaranteed.
If math teachers and English teachers need to fill in for a long time due to special circumstances, or there is a real shortage of teachers, the school should report to the education department in time and recruit teachers as soon as possible. After all, there are specialties in the technical field, and art and music teachers also lack teaching experience in the main courses.