题目内容
Exercise as well as a balanced diet ______ the key to keeping fit.
A. is B. was C. are D. Were
A
考查主谓一致。连接两个主语时,as well as谓语动词和第一个主语保持一致,exercise为不可数名词,故谓语动词用单数形式,有因阐述的是一般性的状态,应用一般现在时。
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