燃油 (rán yóu): fuel oil

This car's fuel is almost used up; we need to refuel at the next service area.

As fuel prices continue to rise, more and more people are choosing to buy electric cars.

The factory's boiler needs regular fuel oil added, otherwise it will affect the production schedule.

The ship's engine suddenly broke down because impurities had mixed into the fuel oil.

The government is promoting the use of biofuel to reduce dependence on traditional petroleum.