use strict;

my $variable_with_a_very_long_name = 1;
print "The value is >>$varaible_with_a_very_long_name<<";

##</code><code>##

# for global variables:
use vars qw(@users $account);

##</code><code>##

for $user (@users) {
    $message = "Hello $user!";
    ...
};

# should become

for my $user (@users) {
    my $message = "Hello $user!";
};