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Some people fear that ________ air pollution may bring about changes in _______ weather around the world.

       A. /; the       B. the; /       C. an; the        D. the; a

A


解析:

pollution是不可數(shù)名詞,air pollution是泛指,所以不用冠詞;后一空格處特指全世界的天氣,用定冠詞。

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