Doctors say that exercise is important for health, but it must be exercise.
A. frequent
B. normal
C. regular
D. usual
网友回答
A. frequent
B. normal
(答案→)C. regular
D. usual
解析:词义辨析题。A.frequent 频繁的 B.normal 正常的 C.regular 有规律的D.usual 通常的 句意:医生说锻炼对健康很重要但是必须是有规律的运动。 根据语意选C