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 ?  
+ _9 v" ^7 C$ t/ Atvb now,tvbnow,bttvb) [/ i0 c8 f" i0 a6 G0 N3 @7 L8 I
thanks in advance.