The H1N1 virus, which is commonly known as swine flu, has spread rapidly around the world since emerging in North America earlier this year, yet still much of what makes it so potent a threat remains a mystery.

VOA: standard.2009.08.25

I don't have any very good answers for that and yet it is one part of the traditional explanation is this, and it's a very important one and much debated, that at a critical time in the battle one technique would be one side would give one great big shove.

我并没有令人满意的答案,目前还有一种传统解释,很重要,同时也饱受争议,那就是在战局千钧一发的时刻,有一项技术就是一方给对方致命一推

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