硬度

例句：

1. 1.The material is very hardness to work with.
   这种材料很难加工。
2. 2. The car has a high hardness rating.
   这辆车的硬度评级很高。
3. 3.The metal is very hardness and cannot be easily cut.
   金属非常坚硬，不容易切割。