He has been in the next room.---Sorry,I thought that he--- i

因为你以为的动作是过去认为,你现在已经知道他在隔壁了,所以用过去时.这是一个题型.如
1---- I am in the same school with you.
----But i thought your were in No 8 school.（原来认为,但现在知道了）
2 ---- Hi,you step on my foot.
------ Oh,sorry ,i didn't know.(现在知道了）