They demanded that the books to the school library right away.A. should returnB. be retur

问题补充：

They demanded that the books to the school library right away.

A. should return

B. be returned

C. were returned

D. returned

答案：

A. should return

(答案→)B. be returned

C. were returned

D. returned

解析：考查固定结构。Demand当要求讲，后面的宾从要用should+do的虚拟语气，should可省，the books和return之间是动宾关系，用被动。所以选B。