Prime Minister Singh criticized the existing global non-proliferation program, saying it has failed to prevent the spread of nuclear weapons.

VOA: standard.2009.09.29

It's an infectious disease; it is spread by--through the air.

它是一种传染病,通过空气传播

耶鲁公开课 - 生物医学工程探索课程节选

It spread throughout the world--the idea of quoting probabilities.

引用概率的这种表述方式很快传遍世界

耶鲁公开课 - 金融市场课程节选

U.S.officials worry that, even if the virus' spread is eventually contained, it could re-emerge months from now during the northern hemisphere's winter flu season, when more than 30,000 Americans die each year from common influenza.

VOA: standard.2009.05.03