elastic stretching

例句：

1. 1. The material is elastic, so it can stretch easily.
   这种材料是弹性的，所以可以很容易地拉伸。
2. 2.When you stretch your arms, the muscles in your back and shoulders are also working.
   当你拉伸手臂时，你的背部和肩膀的肌肉也在工作。
3. 3. The fabric has a lot of elasticity, which makes it comfortable to wear.
   这种布料有很多弹性，穿起来很舒服。