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

after dowload games, how to open it's .mdf n .mds files?1 O+ j5 T0 V9 q) e8 U) }# e
i cant open it?- M; B9 j' I" R! P* I" z6 Y( K* {
pls teach me...TVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。1 X& R; k, _ n- D1 q
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