摘要：逻辑主语
现在分词的完成被动式表示分词的动作发生在谓语的行为之前，且动作由逻辑主语所承受(即与逻辑主语是被动关系)。
【例如】
Having been given such a good chance, he planned to work hard.
Having been experimented several times, this new product will be putsintosmass production.
All the compositionsshavingsbeen written and collected, the teacher dismissed the students.