foreach_in_place.php

<?php

$taxonomies  = array(
    array(
        'name' => 'people',
        'members' => array(
            array('name' => 'Bill Clinton', 'cheater' => true),
            array('name' => 'Barrack Obama', 'cheater' => false),
            array('name' => 'John F Kennedy', 'cheater' => true),
        ),
    ),
    array(
        'name' => 'animals',
        'members' => array(
            array('name' => 'Swan', 'cheater' => false),
            array('name' => 'Hyena', 'cheater' => true),
        ),
    ),

);

foreach($taxonomies as &$taxonomy){
    foreach($taxonomy['members'] as &$member){
        $member['message'] = 'Relax, nothing to worry about';

        if($member['cheater']){
            $member['message'] = "Better keep your eye on this one\n";
        }
        unset($member);
    }
    unset($taxonomy);
}

// Later...

foreach($taxonomies as $taxonomy){
    print strtoupper($taxonomy['name']) . "\n";

    foreach($taxonomy['members'] as $member){
        print "\t" . $member['name'] . "\n";
        print "\t" .  $member['message'] . "\n\n";
    }
}