Many people have come to realize they should go on diet and make room for exerciseA. a;

问题补充：

Many people have come to realize they should go on diet and make room for exercise．

A. a; 不填

B. the; an

C. the; the

D. 不填; an

答案：

(答案→)A. a; 不填

B. the; an

C. the; the

D. 不填; an

解析：考查冠词。固定短语go on a diet节食；exercise锻炼；是不可数名词。句意：很多人认识到了他们应该节食，腾出空间来锻炼。