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

Cchen

after dowload games, how to open it's .mdf n .mds files?
$ S) L4 ]2 {7 `' Q$ N$ v4 \. e% \tvb now,tvbnow,bttvbi cant open it?
- N2 J% Q# R' i5 Z+ W$ [* bpls teach me...公仔箱論壇% b3 t, q4 \* V
tq...