Untitled

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>タイトル</title>
    <script src="jquery-1.4.4.js"></script>
    <p id="first">変更前</p>
    <script>
      $(function(){
        $("p#first").html("<strong>変更後</strong>");
      });
    </script>
  </head>
  <body>

  </body>
</html>