oleum

例句：

1. 1. The painter used oil to paint the portrait.
   画家用油彩画肖像。
2. 2. The old painting is protected with a layer of oil.
   旧画被一层油保护着。
3. 3. Oil is essential for cooking and cleaning.
   油对于烹饪和清洁都是必不可少的。