lumbricin

例句：

1. 1.The engine needs a lubricant to keep it running smoothly.
   发动机需要润滑油来保持顺畅运行。
2. 2. The car has been well-maintained with regular lubrication.
   汽车定期润滑保养得很好。
3. 3.Lubricating oil is used to reduce friction between moving parts.
   润滑油用于减少运动部件之间的摩擦。