say "BUT YOU CAN USE LESS OF THEM :) OR LEARN FROM s/// ";
$trim = join '-',  $orig =~ m{(\w{1,4})\w*}g;
say Dumper $want, $trim ;

##</code><code>##

BUT YOU CAN USE LESS OF THEM :) OR LEARN FROM s///
$want = 'Appl-iPho-4-Blac-Cove';
$trim = 'Appl-iPho-4-Blac-Cove';