All the students were studying in class　　　  Tom;he was playing football on the playground.

A.except　　　　　　　　　　B.besides

C.except for　　　　　　　　D.except on

All the students were studying in class　　　 Tom;he was playing football on the playground.

1. A.
   except
2. B.
   besides
3. C.
   except for
4. D.
   except on