Some majors didn't take math when they took the postgraduate entrance examination. For example, some medical majors got high marks, but later they didn't take math when they took the chemistry exam, so their math lessons became less and less, which was the kind of introduction. Students of general science and engineering or economics have to study mathematics for two years in university, that is, one year of advanced mathematics, a period of linear algebra, a period of probability theory and mathematical statistics. These three courses are compulsory courses for future postgraduate entrance examination. In addition, complex variable function and discrete mathematics are offered according to professional needs, so they will not take the postgraduate entrance examination.