本人任体育教师多年，自制过各种类型的沙包，用于投掷教学，但都易于损坏。去年，我将自己的几条废摩托车内胎缝做了几十个沙包，用作投掷教学，至今完好无损。实践证明，这种橡胶沙包，值得推广。所用的废内胎，可在摩托车修理店里随时捡到别人不要的废胎，然后将胎剪成... I was a PE teacher for many years, made all kinds of sandbags for throwing teaching, but are easy to damage. Last year, I made dozens of sandbags made from several pieces of used motorbike tires for throwing teaching, which have remained intact so far. Practice has proved that this rubber sandbags, it is worth promoting. The waste tube used in the motorcycle repair shop at any time picked up the tires that others do not want, and then cut into ...