It's not what you do once in while but what you do day in and day out that makes difference.
A. the ; /
B. / ; a
C. a; a
D. the; a
网友回答
A. the ; /
B. / ; a
(答案→)C. a; a
D. the; a
解析：考查冠词。固定词组in a while=in a moment=in a minute=soon=at once=right away 立刻 马上；make a difference有影响，起作用；day in and day out每天，一天又一天；本题是一个强调主语的强调句型。句意：起作用的不是你马上要做的事情而是你每天所做的事情。