机械波概念的抽象性和波动情境的多样性 ,是本章教学的难点内容 .因此 ,理解波的特征 ,不仅可以深化对波的本质的理解 ,而且也是掌握分析波动问题的有效方法 .本文将对此作进一步分析 .波动的特征一　沿波的传播方向 ,各质点的运动特征是先振动的质点依次带动后振动的质点的运 The abstraction of the concept of mechanical waves and the diversity of fluctuating situations are difficult aspects of teaching in this chapter. Therefore, understanding the characteristics of waves not only can deepen the understanding of the nature of waves, but also can be an effective way to grasp the problems of analyzing fluctuations. For further analysis, the characteristics of the fluctuations, along the propagation direction of the wave, are the movement characteristics of each particle.