It's not what you do once in while but what you do day in and day out that makes differe

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

A. the ; /B. / ; a(答案→)C. a; aD. 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。

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