About 500 cars in the factory last month.A. were producedB. are producedC. produceD. produ

问题补充：

About 500 cars in the factory last month.

A. were produced

B. are produced

C. produce

D. produced

答案：

(答案→)A. were produced

B. are produced

C. produce

D. produced

解析：此题重点考查一般过去时的被动语态的基本结构。