1.having been done即所谓的过去分词的完成形式,它不能做（后置）定语,但是可以做状语. 如：Having been admitted into Tsinghua University,he decided to treat himself to a big dinner with his whole family. （已经）被清华大学录取之后,他决定和家人举行大宴以犒劳自己. 2.如果要用表示已经被完成的动作的非谓语动词来做后置定语的话,只需要直接使用done（过去分词）即可. 如：Did you attend the meeting held yesterday? 你参加了昨天举行的会议了吗?
