My situation is similar to his, and it was always like this in middle school. I got good grades in math, but most of the points I lost were not because I couldn't do it, but because of my calculation and carelessness. To be honest, this situation will not be eradicated overnight, but some measures can be taken to remedy it. Psychological aspects are very important, just like me, trying to put an end to this kind of mistake. I always turn over and over a question, and the result is right, but time is running out, which is not appropriate, because I will psychologically suggest that I may have miscalculated. As a result, the more mistakes he makes, in view of his frequent mistakes, it is necessary to find out the reasons for his frequent mistakes. First, he felt good about himself and relaxed his seriousness. The second is to worry that there is not enough time and rush to calculate. These are all psychological reasons. Therefore, it is very important to have a problem-solving mentality. Don't float, but don't be impatient. You know, you have to take it step by step in order to get more deserved points safely.