请问怎样用subtitile的file (sub) ??

alantct

i hv a movie file, Lelio.Po.Po.2010.DVDRip.XviD.ONiE and another two files (seprate) is the sub  & idx file. may i know how to use or combine the video file so that i can watch it with subtitle ?  
% h8 y" `' h- r/ N8 d公仔箱論壇
5 w7 c% R3 m' b1 f3 Utvb now,tvbnow,bttvbthanks in advance.