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By Mil Arcega Washington, DC 28 April 2006 watch Mass Transit report Metrobus powered by hybrid electric technology Bus companies in the United States are reporting an increase in ridership as high fu
2006年VOA标准英语（四月）
By Carol Pearson Washington 22 August 2007 High blood pressure, or hypertension, is a disease usually associated with adults, but children can get it too and can have serious health problems because of it. A new study is now calling for pediatricians
2007年VOA标准英语（八月）
The X-ray image revealed how the black hole at the heart of the galaxy was firing unimaginable amounts of radiation into surrounding space and with extraordinary consequences. We could see what was going on at the centre and we could start to underst
探索与发现2013年
Was there any connection between the two? What Magorian discovered was completed unexpected. The relationship that we find was essentially that the bigger the galaxy, the bigger the black hole. That's in its broad terms. If you want to be a bit more
探索与发现2013年
By Melinda Smith Washington 12 September 2007 A recent study indicates that a disturbing number of American children with high blood pressure go undiagnosed. The study has prompted discussion worldwide about whether hypertension among children is jus
2007年VOA标准英语（九月）