#!/usr/bin/perl -wT

use strict;

#get inserted text
my @inserted_text = ('Blah','Blah Blah');

# read in the file
open (FILE,"filename") or die "Can't open file";
my @file = <FILE>
close(FILE)

open (OUTFILE,">filename") or die "Can't open file";
my $line = 0;
foreach(@file) {
    if ($line = 569) {
       foreach(@inserted_text){print OUTFILE;}
     }
    $line++;
}
close(OUTFILE);