Unlike steel, copper or aluminum, the profit margin on tungsten sales was very low or there was no profit at all and export sales could not help the producers.是什么意思_Unlike steel, copper or aluminum, the profit margin on tungsten sales was very low or there was no profit at all and export sales could not help the producers.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句