单词：variable density tunnel
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By Caty Weaver Broadcast: July 25, 2003 This is Bill White with the VOA Special English Environment Report. Researchers say they have found a way to reduce the cost of some 1)fuel cell production. The
VOA2003（下）-环境与健康
For something that could revolutionize the world, its come along very slowly. The fuel cell was invented in 1839, but there was little development until the 1950s when NASA started to use them in space where they are still used today. Now, after yea
国家地理2008年
By Paul Sisco Washington 17 April 2008 Federal regulators in Washington have approved plans to upgrade the nation's Emergency Alert System to include text messages to cellphones and other mobile devices. VOA's Paul Sisco has more in this Searching fo
VOA常速英语2008年（四月）
WASHINGTON, Aug. 4 (Xinhua) -- Researchers have found a way to turn mouse embryonic stem cells into sperm and this finding opens up new avenues for infertility research and treatment, according to astudy published Thursday in the online edition of jo
英语新闻
Turn Off Your Cell Phone 关掉你的手机 We went to the movie the other night. I sat in an aisle seat as I usually do, because it feels a little roomier. Just as the feature was about to start, a blonde from the center of the row got up and starte
趣味英语
WASHINGTON, May 11 (Xinhua) -- Researchers at Brigham and Women 's Hospital (BWH), a teaching affiliate of Harvard Medical School, have identified(鉴定) a human lung stem cell that is self-renewing and capable of forming and integrating multiple bi
英语新闻