The blackboard is _______ the wall(?).

   It is_________ in the wall.

 A. on, not       B. on, /                 C. in, no

The blackboard is ____ the wall.　　　

[　　]

A.in　　　B.at　　　C.on　　　D.behind

There is a blackboard ________ the wall.

1. A.
   under
2. B.
   at
3. C.
   in
4. D.
   on

There is a blackboard __________ the back of our classroom.It is ______ the back wall.

1. A.
   on/in
2. B.
   in/at
3. C.
   at/on
4. D.
   at/in