按传统方法,正、反比例是分别教学的。这样教的缺点是:学生学习正比例时,概念清晰、判断正确,但学习反比例以后,就开始出现概念混淆、判断经常出错的现象,尽管教师反复讲解、对照,也无多大收获。析其原因,主要在于分别教学时,练习十分单一,学生不需动脑分析,便可按例题模式 According to the traditional method, positive and negative ratio are taught separately. The disadvantage of this teaching is that when the students are studying proportionally, the concepts are clear and the judgments are correct. However, after learning the inverse proportion, confusion in concepts and frequent mistakes in judgments have taken place. Although teachers repeatedly explain and contrast, there is not much gain. Analysis of the reasons, mainly when teaching separately, the practice is very simple, students do not need brain analysis, you can press the example mode