短语词组短語forced -draft fan 鼓風扇;鼓風機;送風機forced d draft condenser 強制通風式冷凝器stratified forced -draft 分層送風forced d draft fan 強制通風風扇;鼓風機forced air draft oven 強制通風爐forced d draft blower 強制通風鼓風機 返回 forced draft