use warnings;
use strict;

my @deleted = ('Entry 1', 'Entry 2', 'Entry 3');
my $str = "Deleted forum";
@deleted > 1 ? ($str .= 's: ') : ($str .= ': ');
$str .= join ', ', @deleted;
print $str;

##</code><code>##

Deleted forums: Entry 1, Entry 2, Entry 3