There exist great quantity of bird flu bacterium in the environment in which the humankind lives.

人类生存的环境中大量存在着禽流感病毒，人类的生产生活活动增加了感染禽流感的机会。

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There exist great quantity of bird flu bacterium in the environment in which the humankind lives.

人类生存的环境中大量存在着禽流感病毒，人类的生产生活活动增加了感染禽流感的机会。

youdao