By the time Mr Wang returned home from Beijing his son's wedding .A. ended　　　　　　　　B. has

问题补充：

By the time Mr Wang returned home from Beijing, his sons wedding .

A. ended

B. has ended

C. had been ending

D. had ended

答案：

A. ended

B. has ended

C. had been ending

(答案→)D. had ended

解析：考查时态。by+过去时间，主句用过去完成时，by+将来时间，主句用将来完成时。根据returned可知，这里是指过去的时间，故主句用过去完成时，排除A、B；end“结束”，是短暂性动词，不能用于现在完成进行时，排除C，故选D。