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n.（全國或全球性）流行病，大流行病( pandemic的名詞復(fù)數(shù) )...

pandemics的音標(biāo)：...

Periods when diseases spread around the world are called pandemics.疾病在全世界范圍內(nèi)傳播時(shí)期稱為大流行.Since then, there have been a total of eight cholera pandemics.從那時(shí)開始, 霍亂大流行總共爆發(fā)過8次.Previous pandemics have been characterized by waves...