<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>helloInterpolation</title>
</head>
<body>
<?php
$firstName = "John";
$lastName = "Doe";
print "Hello $firstName $lastName!";
?>
</body>
</html>