第2个回答 2016-10-10
1、had been +动词ed 是过去完成时的被动语态。强调动作的承受者。
如:
1).The bridge had been built by the end of last year .
到去年年底为止这座桥建成了。
2). The food had been eaten when we got there .
当我们到达那里的时候食物都被吃光了。
2、had+动词ed 是过去完成时态。表示过去的过去已经完成或发生了的动作。
如:
1). The train had left when they got to the station.
当他们到达车站时火车已离开了。
2). We had learned two units by the end of last week .
到上周为止我们学了两个单元。