短語詞組短語external air source 外部氣源external heat source 外來的熱源external radiation source 體外輻射源external noise source 外界噪聲源steam external heating source 對外供熱汽源external voltage source 外部電壓源external clock source 外部時(shí)鐘源;外部時(shí)鐘信號源external perimysium source 外部信源 返回 external source