past perfect
n.
Tense formed with the past tense of "have" and a past participle, as I had seen.
【文法】过去完成式。
青年旅行网英语在线翻译词典收录了86352条英语词汇在线翻译词条,基本涵盖了全部常用英语词汇的中英文双语翻译及用法,是英语学习的有利工具。