All your intership are belong to us

yada.php

<?php
    function get_catchphrases() {
        $catchphrases = array(
            'progressive-enhancement',
            'semantic-markup',
            'mobile-first-development',
        );

        $catchphrases = implode(', ', $catchphrases);
        $catchphrases = substr_replace($catchphrases, ", and ", strrpos($catchphrases, ", "), strlen(", "));
        return $catchphrases;
    }

    function recognize($headphones) {
        return $headphones ? "yes" : "no";
    }

    function friends() {
        $friends = array(
            'the internet',
            'a cat',
            'HTML',
            'coffee',
            'CSS',
            'JavaScript',
        );

        $count = count($friends);
        $index = rand(0, $count);
        return $friends[$index];
    }
?>

<p>
    Your catchphrases are <?php echo get_catchphrases(); ?>.
</p>
<p>
    <?php $headphones_on = false; ?>
    <strong>Q</strong>: You're <?php echo $headphones_on ? "" : "not"; ?> wearing headphones. Do people recognize you?<br>
    <strong>A</strong>: <?php echo ucfirst(recognize($headphones_on)); ?>
</p>
<p>
    Your best friend is <?php echo friends() ?>.
</p>