primary air fan

例句：

1. 1. The primary air fan is designed tocool the room quickly.
   初级风扇设计用来快速冷却房间。
2. 2. The primary air fan hasa low noise level, making it suitablefor use in bedrooms.
   初级风扇噪音低，适合卧室使用。
3. 3. The primary air fanis an essential appliance for summerhomes.
   初级风扇是夏季房屋必备的电器。