seal oil

例句：

1. 1. This seal oil is very effective at preventing leaks in the seals.
   这种密封油在防止密封处泄漏方面非常有效。
2. 2. The seal oil was used to lubricate the moving parts of the machine.
   密封油被用来润滑机器的移动部件。
3. 3. In ancient times, seal oil was often used as a preservative for wooden objects.
   古代，密封油常被用作木制品的防腐剂。