题目内容：

Upon arriving home,I was surprised to find the papers I had had ______ was missing.
A.to collect B.collected C.it collected D.to be collected
请详细说出理由.thanks!

优质解答

I had had ______ 是定语从句, 前面省去了个that即： （that) I had had 【collected】 that 这个关系代词代先行词the papers, 作had had（have这个使役动词的过去完成时）的宾语：可见： 此句型为：have sth done...

追问：

能告诉我这句话的完整意思吗？thanks！！！

追答：

一到家， 我惊讶地发现我所收集的文件全不翼而飞了。