问题补充：
He didn’t tell me .
A. which floor did he live on
B. which floor he lived on
C. which floor he lived
D. Which he lived on the floor
答案：
A. which floor did he live on
(答案→)B. which floor he lived on
C. which floor he lived
D. Which he lived on the floor
解析：句意：他没有告诉我它住在哪一层。在宾语从句的位置上使用陈述句语序，不用疑问句语序，所以选B。
