แสดงผล title ทำแบบข้างบนได้แล้วครับ แล้วส่วนของ title , Keywords และ Description

<?
header('HTTP/1.1 200 OK');

echo "Now URL = ".$_SERVER['REQUEST_URI'];


//*** Link Page ***//
echo "<hr>";
echo "<a href=/hello.html>Hello PHP</a> , <a href=/config.html>Config PHP</a> , <a href=/install.html>Install PHP</a>";
echo "<hr>";


//*** Include Content ***//

if($_SERVER['REQUEST_URI'] == "/hello.html")
{
$title="";
$Keywords="";
$Description="";
	require("hello.php");
}
elseif($_SERVER['REQUEST_URI'] == "/config.html")
{
$title="";
$Keywords="";
$Description="";
	require("config.php");
}
elseif($_SERVER['REQUEST_URI'] == "/install.html")
{
$title="";
$Keywords="";
$Description="";
	require("install.php");
}
else
{
	// Default include;
}
?>