一个英语句子的省略情况
Mrs.White showed her students some old maps（borrowed from the library）.
括号里的是后置定语,是定语从句的省略,请补充完整.
我觉得应该是Mrs.White showed her students some old maps WHICH HAD BEEN borrowed from the library）.因为先要借来，在给同学们看。有时间的先后顺序