Help!!! how to open .mdf n .mds files?

Cchen

after dowload games, how to open it's .mdf n .mds files?
5 D% h( y: C& D" C0 Gi cant open it?
9 |0 z9 v; z& W4 P公仔箱論壇pls teach me...tvb now,tvbnow,bttvb$ p; [' C$ u3 R0 S; X) C  \- y
tq...