preheated air

例句：

1. 1. The car engine needs to be preheated before starting the engine.
   汽车发动机启动前需要预热。
2. 2.The pilot had to preheat the cabin air conditioning system before takeoff.
   飞行员在起飞前必须预热客舱空调系统。
3. 3.During the winter, it's important to preheat the air before going outside.
   冬天外出前，重要的是先预热空气。