木材、煤炭、石油、汽油和天然气都是不同种类的燃料。

Wood, coal, oil, petrol and gas are all different kinds of ___fuel.

我的车使用无铅燃料时运行状态最佳。

My car runs best on unleaded ___fuel.

降低车速可以减少燃料消耗。

Reducing your speed can lead to lower ___fuel consumption.