The workers were made all day and all night by bosses in the old days.A. workB. workingC.

问题补充：

The workers were made all day and all night by bosses in the old days.

A. work

B. working

C. worked

D. to work

答案：

A. work

B. working

C. worked

(答案→)D. to work

解析：考察句式be made to do sth 被要求做某事，故选D。