1, you've been getting 90 points, which shows that you don't understand and use some concepts, definitions and formula details well (such as the definition of functions, the understanding of the sum-product formula, triangles, dihedral angles, etc.). I suggest you understand the questions in the book first, and then review the materials and papers.

2. Make a plan when making a book and allocate time reasonably.

3. After each exam, summarize it; Where do you lose points every time? Focus on reading. It is best to compare the papers of the previous five exams;

4. After reviewing the books, do more simulation papers, starting with simple volumes; Good luck!