教后记许卫华“百分数的意义和写法”是在“分数意义”的基础上学习的，它是学习百分数应用题的基础。百分数又是比的一种特殊形式，对学习“比的意义”有直接影响。为了使学生能较好地理解、掌握这一内容，教学时我从学生熟悉的实际事例出发，遵循概念教学的原则，由感性... Teaching Postscript Xu Weihua “meaning and writing of the percentage” is based on the “meaning of scores” to learn, it is to learn the basis of the percentage of application questions. Percentages are also a special form of ratio that has a direct impact on learning “the meaning of ratio.” In order to enable students to better understand, grasp the content, teaching, I learned from the students are familiar with the practical examples, follow the principle of conceptual teaching, by the sensibility ...