#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;

PrintInRevWordOrder ("The tall brown cat walked down the alley-way.");

sub PrintInRevWordOrder {
  my @string = split /\s+/, shift;
     # the problem says this is to be passed as an argument
     # but you are using global variable.  bad practice in general.

     # C-stlye for loop ... usually I use more perl-esque structures,
     # but hey -- TMTOWTDI (there's more than one way to do it!)
  for (my $i = $#string; $i > 0; $i--) {
    print $string[$i], " ";
  }
}