<first:html xmlns:first="http://www.w3c.org/1999/xhtml">

    <first:head>
        <first:title>A really bad idea</first:title>
    </first:head>

    <first:body>
        <first:h1>A really bad idea</first:h1>
        <first:pre>
            <second:pre xmlns:second="http://my.com/namespaces/test-data">
                <second:table>
                    <second:data>
                        Hello World
                    </second:data>
                </second:table>
            </second:pre>
        </first:pre>
    </first:body>
</first:html>