sign of rubber stick

例句：

1. 1. This is a sign of the rubber stick we found in the park yesterday.
   这是我们昨天在公园找到的橡胶棒的标志。
2. 2.The teacher used a rubber stick to illustrate the concept of force.
   老师用橡胶棒来说明力的概念。
3. 3. The artist used a rubber stick to create a unique piece of art.
   艺术家使用橡胶棒创作了一件独特的艺术作品。