What happened to the most arrogant person you know?

One of my high school classmates. My classmate is crazy and full of knowledge, but he can't get ideal results in every exam, which not only makes him very upset, but also makes the teacher very anxious. His madness is mainly manifested in brushing the questions, and his speed of brushing the questions is dumbfounded. He can spend the whole afternoon brushing the questions, and basically he can finish the whole set of papers in one afternoon. He is not the kind of person who brushes questions inefficiently. He can memorize the results of every problem he has done, especially science and mathematics, and he is very interested. After giving examples in class, the teacher will mostly do it the first time, but he will always encounter such and such problems in the exam because he has encountered many problems.