Multiple inheritance through PHP using traits

I actually took this code from http://php.net. Multiple inheritance has always been a bit dodgy for me in PHP. This is an excellent example of how to use traits to achieve it.

<?php
trait Hello {
    public function sayHello() {
        echo 'Hello ';
    }
}

trait World {
    public function sayWorld() {
        echo ' World';
    }
}

class MyHelloWorld {
    use Hello, World;
    public function sayExclamationMark() {
        echo '!';
    }
}

$o = new MyHelloWorld();
$o->sayHello();
$o->sayWorld();
$o->sayExclamationMark();>
?>