My father is usually on duty in his office every few days.A. the；aB. /； /C. /；aD. a； /

问题补充：

My father is usually on duty in his office every few days.

A. the；a

B. /； /

C. /；a

D. a； /

答案：

A. the；a

(答案→)B. /； /

C. /；a

D. a； /

解析：考查冠词的用法。句意“我爸爸每几天就在办公室值班。”on duty“在值班”；every few days“每几天”。every“每......”，后不与冠词连用。故选B。