The agency provides protection and assistance to more than one-half million Somali refugees in the nearby countries of Kenya,Yemen,Ethiopia, Djibouti and Uganda.

VOA: standard.2009.09.26

And they did this by taking-- they recognized that somehow, if you had a mild exposure to the disease, your body could then develop protection against more severe forms of the disease.

他们通过用,他们通过某种方式意识到,如果较轻微地得过这种病,你的身体会发展保护机制,来抵挡更为严重的疾病

耶鲁公开课 - 生物医学工程探索课程节选

U.S.Customs and Border Protection inspectors in El Paso,Texas are giving more scrutiny to people entering the United States on foot and in vehicles.

VOA: standard.2009.04.30

The final Earth Day themed event took place Sunday. The Environmental Protection Agency, students and other organizations with ideas for a more sustainable future filled large white tents on the mall.

VOA: standard.2010.04.25