Nancy spent half an hour playing the piano every day.A. practiceB. practicingC. to practi

问题补充：

Nancy spent half an hour playing the piano every day.

A. practice

B. practicing

C. to practicing

D. to practice

答案：

A. practice

(答案→)B. practicing

C. to practicing

D. to practice

解析：句意：Nancy 每天花半小时练习弹钢琴。spent 的原形是spend，spend sometime doing sth.花费时间做某事。故用动词的ing形式，故选B。