This is probably a state of contemporary college students before exams, but this phenomenon is very common. You can't say bad or good. I feel terrible. After all, knowledge needs to be accumulated for a long time, rather than cramming for it temporarily. Before the exam, I tried to cram knowledge into my mind, but the knowledge was not integrated and mixed together. Once you are nervous in the examination room, you are prone to temporary amnesia before the exam. It may also lead to insufficient rest time and insufficient energy during the exam.