>can anyone explain to me what are these numbers refer to? in recout.mlf file

these are described in the HTK manual, chapter 6.2.1 HTK Label Files:

Each line of a HTK label file contains the actual label optionally preceded by start and end times, and optionally followed by a match score.

     [start    [end] ] name [score] { auxname [auxscore] } [comment]

where start denotes the start time of the labelled segment in 100ns units, end denotes the end time in 100ns units, name is the name of the segment and score is a floating point confidence score. All fields except the name are optional.

thanx a lot