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 ?  
% L$ {1 ]% L$ r3 Y: m! I0 Q5 f" D% C公仔箱論壇tvb now,tvbnow,bttvb: s1 D. ^' e1 w- {- {) ?9 E
thanks in advance.