— Where did you find your lost key?

   — Well, it was at the hotel         we stayed.

    A. that         B. where            C. when         D. in what

 Do you know the professor in        home we stayed?

   A. which          B. his             C. whose            D. whom

— Where did you find your lost key?

   — Well, it was at the hotel         we stayed.

    A. that         B. where            C. when         D. in what

 Do you know the professor in        home we stayed?

     A．which                 B．his                      C．whose                D．whom

Do you know the professor in        home we stayed?

     A．which       B．his    C．whose      D．whom