问题补充：
This is the hotel last month.
A. which they stayed
B. at that they stayed
C. where they stayed at
D. where they stayed
答案：
A. which they stayed
B. at that they stayed
C. where they stayed at
(答案→)D. where they stayed
解析：where是关系副词，表示地点，在定语从句中作地点状语。
