灯泡的故事
爱迪生100多年前发明了钨丝灯泡，到现在，这些旧式灯泡将推出历史舞台http://t1.g.hjfile.cn/voa/rm/2007/03/20070320.mp3Thomas Edison perfected the incandescent light bulb 128 years ago... lighting up a nation and the world ever since. Many would have those bulbs switched off today and replaced with compact fluorescent bulbs that are up to 70 percent more efficient. Environmentalist Mike Tidwell,…
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