正视学生概念学习的困难,在具体情境中,借助学生已有知识背景和生活经验,利用分类思想,使抽象的概念形象化,便于学生理解和掌握。分类中的逐级分类,逐级讨论,可以使学生思维互补深入。应用分类,可以化整为零,对每个子类的情况分别讨论,各个击破,再合零为整,可以使看似复杂的问题变得简单。 Faced with the difficulty of the concept of learning students, in the specific context, with the students have the knowledge background and life experience, the use of classification ideas, the abstract concept of visualization, to facilitate students to understand and master. Classification of the gradual classification, step by step discussion, you can make students thinking complementary depth. Application classification, can be adjusted to zero, respectively, for each subcategory of the situation were discussed, each break, and then zero for the whole, you can make the seemingly complex problem becomes simple.