That's because you don't have the thinking to solve problems, so you are slow. Generally, everyone will form their own problem-solving thinking before senior three, and then practice systematically in senior three to form problem-solving thinking. At that time, when I saw a question, I wrote down the understanding method without thinking. The question was naturally done and the reaction speed was very fast. You are slow now because you haven't studied the solutions to various problems before, so every time you try to do it, it will naturally be slow. The method is also very simple, that is, summarize the wrong questions and slow questions I have done before into a wrong book, and find my own weaknesses and solutions. If you have anything else, just ask.