合运动与分运动的关系既形象又抽象,容易使学生“陷”进去而无法自拔,如何引导学生走出对合运动与分运动的关系的困惑就尤为重要了。说它“形象”是因为有小船渡河、平抛运动等例子来理解,说它“抽象”是因为这些例子也很难“看到”分运动的“存在”。 It is particularly important that the relationship between movement and sub-movement is both abstract and image-oriented, and it is easy for students to “get stuck” and can not extricate themselves. How to guide students to get out of the confrontation between sub-movement and sub-movement is particularly important. It is said that “Image ” is because there are boats crossed the river, flat throwing exercise and other examples to understand that it “abstract ” because these examples are also difficult to “see ” sub-movement “existence ”.