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 ?  
. n9 r0 K! W% d! [tvb now,tvbnow,bttvbtvb now,tvbnow,bttvb: p) A$ ^; O3 a# W6 {
thanks in advance.