gas /ɡæs/ n.［c］&［u］气体；煤气；汽油：waste gas废气; step on the gas 踩油门；加速The gas which the factory gave off polluted the air.这家工厂排放出的气体污染了空气。The building was furnished with gas tubes.这座大楼装上了煤气管道。Air is a mixture of several gases.空气是很多种气体的混合物。