问题补充：
Upon arriving home, I was surprised to find the paper I had had was missing.
A. to be prepared
B. to prepare
C. preparing
D. prepared
答案：
A. to be prepared
B. to prepare
C. preparing
(答案→)D. prepared
解析：考查have sth done“请人做，使…被做”词组，分析句子the paper后面是定语从句，两个had，一个是助动词，一个是使役动词，在定语从句中从当宾语的关系代词被省略，prepare和the paper是被动关系，选D，意为：一到家，我很惊讶的发现我准备好的文件不见了。
如果觉得《Upon arriving home I was surprised to find the paper I had had was missing.A. to be prep》对你有帮助，请点赞、收藏，并留下你的观点哦！
