Alice bent losing weight increased the time of exercise to three hours a time.A. on; i

问题补充：

Alice, bent losing weight, increased the time of exercise to three hours a time.

A. on; in

B. on; for

C. with; for

D. with; at

答案：

A. on; in

(答案→)B. on; for

C. with; for

D. with; at

解析：考查固定短语。Be bent on热恋于;for a time暂时，一度；at a time一次。.句意：热恋于减肥的Alice,一度把锻炼的时间增加到三个小时。