—Have you been watching TV? Don’t valuable time running.—I’m not. I’m tired now and only a

问题补充：

—Have you been watching TV? Don’t valuable time running.

—I’m not. I’m tired now and only am taking a short break.

A. give

B. waste

C. cost

D. spare

答案：

A. give

(答案→)B. waste

C. cost

D. spare

解析：题意：别浪费宝贵的时间跑步。give给；cost花费；spare抽出(时间)，都与题意不符。