$tpl = 'путь к шабу';
require $tpl;
Далее вывод 1.
$tpl = 'путь к шабу';
require $tpl;
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<!--[if lt IE 9]><script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![ endif]-->
<title></title>
<meta name="keywords" content="" />
<meta name="description" content="" />
<link href="./templates/css/style.css" rel="stylesheet">
</head>
<body>
<div class="wrapper">
<header class="header">
<strong>Header:</strong>
</header><!-- .header-->
<div class="middle">
<div class="container">
<main class="content">
<?= include $tpl ; ?>
</main><!-- .content -->
</div><!-- .container-->
<aside class="left-sidebar">
<div class="left_menu">
<ul>
<li><a href="./new_company">Новый клиент</a></li>
<li><a href="./manager_static">Статистика</a></li>
</ul>
</div>
</aside><!-- .left-sidebar -->
</div><!-- .middle-->
</div><!-- .wrapper -->
<footer class="footer">
<strong>Footer:</strong>
</footer><!-- .footer -->
</body>
</html>
<form class="form-signin" role="form">
<h2 class="form-signin-heading">Вход</h2>
<input type="email" class="form-control" >
<input type="password" class="form-control">
<br />
<button class="btn btn-lg btn-primary btn-block" type="submit">Войти</button>
</form>