问题补充:
His father told me that he for the United States three days .
A. has left; ago
B. had left; ago
C. left; ago
D. had left; before
答案:
A. has left; ago
B. had left; ago
C. left; ago
(答案→)D. had left; before
解析:考查过去完成时,句意是:他爸爸告诉我他三天前去了美国。说明在他爸爸告诉我前他去了美国,用过去完成时,和过去完成时连用表示“三天前”用three days before,表示过去某个时间前的三天,选D。