hard genuine babbitt alloy

例句：

1. 1. The car is hard to start in the cold weather.
   这辆车在冷天气里很难启动。
2. 2. The rocks are hard and unyielding.
   这些岩石坚硬且不可弯曲。
3. 3. The metal is hardened by heat treatment.
   金属通过热处理变得坚硬。