单词：cement floor
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By Carol Pearson Washington 30 April 2008 Ten years ago, the U.S. Food and Drug Administration approved LASIK, eye surgery with a laser that enables people to see without glasses. But about five percent of LASIK procedures fail, and those patients ca
VOA常速英语2008年（四月）
Many people remember the colors of the rainbow by the acronym ROY G. BIV. For red, orange, yellow, green, blue, indigo and violet. Well, the color indigo just made news. Indigo gets its name from the plant Indigofera tinctoria and its relatives, whic
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Delay - This is the wait time between to specific events, and regarding satellite communications, it is the time it takes for a signal to go from the transmission station up to orbit and through the s
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DEVELOPMENT REPORT - Bringing Color to Life With Natural Dyes By Jill Moss Broadcast: Monday, August 15, 2005 I'm Barbara Klein with the VOA Special English Development Report. Dye can bring a little
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By Paul Sisco Washington 14 November 2007 At the McDonald Observatory in western Texas, a unique space program has been quietly underway for more than 30 years. It is called the Lunar Laser Ranging Program. VOA's Paul Sisco has more. Research scienti
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An investigation has revealed six garment manufacturers in Shanghai have made school uniforms using toxic dye. The city's quality watchdog says it found aromatic amine dye in uniforms sold to 21 primary and middle schools across the city. China's nat
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