lubricant thickening

例句：

1. 1. The oil is thickening in the pan.
   油在锅里变浓了。
2. 2. The water has started to thicken as it cools.
   水开始冷却时变浓了。
3. 3. The dough is starting to thicken as it rises.
   面团开始上升时变厚了。