Hi again,
Thanks for your very prompt reply but it is the words that are adjacently repeated that I want to print. I can do this part, but what my script does is print out all these repeats instead of just showing the repeat once, so for example if a line contains the word hello eight times in a row, i only want this word to show once. here's my script.
I will be very grateful for your help. Thank you!!

#!/usr/bin/perl

# rcwords.pl: print immediately adjacent repeated words once from inpu
+t,
# even if they are repeated more than once,
# and print out these words along with the line number(s) that they ap
+peared.

use English;
use diagnostics;

$prevword = '';
$n = 0;

while ($line = <>) {

    $n = $n + 1;
    $line =~ s/[[:punct:]]/ /g;
    $line = lc $line;
    @words = split /[[:space:]]+/, $line;

    foreach $word (@words) {

        if ($word ne '') {

            if ($word eq $prevword) {
            unless ($prevword eq $prevword) {
                print " $n $word\n";

            }
            }
            $prevword = $word;
        }
    }
}
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