There are fifty students in our class, of the boys footballA. two third; likes B. two

There are fifty students in our class, of the boys football.
A. two third; likes B. two thirds; like C. two thirds; likes

解析：基数词+序数词的适当形式，表示分数，作主语时，根据其后接的词而定，如果为不可数名词，则相当于单数，如果其后接的为可数名词复数形式，则相当于复数，故选B

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