This question is a bit difficult. The key is that the information given by the topic is different from that given in peacetime, which makes it impossible to quickly respond to what the test center is. In 2022, when there are many new questions in the math volume, it will be difficult, and sometimes it will even be wrong. In fact, the main reason is that the foundation is not solid at ordinary times, and the lack of thinking is not fully understood. I just want to brush the questions, not take the exam.