在1986年，世界上大约有4千万台电脑，到2006年，数字已经上升到8亿，在20年中增长了20倍。关键词汇：twenty-fold：20倍；decade：20年。这句话的翻译难点是数字的记录，考生还是把数字记成40million：40m，800millio

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In 1986, there were over 40 million computers in the world, while by 2006, that number climbed to about 800 million—a twenty-fold increase in two decades.