Use the H key to speed up the subtitle display or the G key to delay it by 50 milliseconds per tap.
Find community-uploaded SRT files on Subscene by searching for "Persian Lessons".
Use the F1 key to delay the subtitles and the F2 key to speed them up.
Look for subtitle files with .SRT or .ASS extensions containing .BDRip , .BRRip , or .BluRay in the filename.