The World Health Organization says swine flu has reached 160 countries globally but it s still in its early stages and could infect 2 billion people over the next two years.是什么意思_The World Health Organization says swine flu has reached 160 countries globally but it s still in its early stages and could infect 2 billion people over the next two years.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句