Node/Element/insertBefore.html

<!DOCTYPE html>
<html>
<head>
  <meta content="text/html;charset=utf-8" http-equiv="Content-Type">
  <title>insertBefore</title>

  <style type="text/css">
    b {color: red}
  </style>

</head>

  <script type="text/javascript">
    function main() {

       var div = document.getElementById('theDiv');

       var created=document.createElement('span');
       created.innerHTML=' <b>created</b> ';
       div.insertBefore(created, div.childNodes[4]);


    }
  </script>

<body onload='main();'>

  <div id='theDiv'><span>one</span> two <span>three</span> four <span>five</span> </div>


</body>
</html>