题目内容：

The workers were made___day and night.
A to work B work C working D worked 选择A 但是为什么啊

优质解答

A to work
当谓语动词是make,let,see,hear等动词时,做宾语补足语的不定式要省去to；但是用于被动语态时,to就不能省略了.再如：
We saw Tom come into the roo..
Tom was seen to come into the room.