在数学学习过程中，学生难免出错．重要的是教学中教师要多想学生之所想，特别应想学生所错．这是为学生可持续学习创造良好条件的关键．一方面教师要预想“学生在哪儿易错”，准确把握易错点，并着力当好学生避免错误的决策者；另一方面要想“学生在哪儿已错”，及时把握... In mathematics learning, students are inevitably mistaken. It is important that teachers in teaching should think more about what the students think. They should especially think about mistakes made by students. This is the key to creating good conditions for students’ sustainable learning. On the one hand, teachers should anticipate “Where are the students’ mistakes?” and accurately grasp the error-prone points, and try to be a good student to avoid the wrong decision makers. On the other hand, we must think “Where are the students wrong?”