The defense works_________long ago to keep the enemy away.A.were built B.has bee

admin2020-12-24  1

问题 The defense works_________long ago to keep the enemy away.

选项 A.were built
B.has been built
C.had been built
D.was built

答案D

解析考查动词时态和主谓一致。主语The defense works(防御工程)是集合名词,当成整体考虑,谓语动词要用第三人称单数形式。long ago表示过去的时间,所以用一般过去时态的被动语态。故选D。
转载请注明原文地址:https://ti.zuoweng.com/ti/VoT8KKKQ