a(an)⁷
人文科学

        a lamp【问】 The gas-filled tungsten filament lamp is more of a furnace than a lamp. Since it uses ninety per cent of the power to produce unwanted heat and uses only ten percent to makelight.[原译]这种充气钨丝灯与其说是一盏灯,不如说是一个火炉。因为它耗去90%的电能去......（本文共 840 字）     [阅读本文] >>