verify.php

<?php

// call the lib..
require_once('recaptchalib.php');

// Get a key from http://recaptcha.net/api/getkey
$publickey = "";
$privatekey = "";

# was there a reCAPTCHA response?
	if ($_POST["submit"]) {
    		$response = recaptcha_check_answer($privatekey,
	  	 	 $_SERVER["REMOTE_ADDR"],
	  	 	 $_POST["recaptcha_challenge_field"],
	  	 	 $_POST["recaptcha_response_field"]);
	  	  
        if ($response->is_valid) {
        		# Valid reCAPTCHA response here
				echo "Yes, that was correct!";
        } 
        else {
      			# set the error code so that we can display it
				echo "Eh, That wasn't right. Try Again.";
    	}
	}
?>

<form action="verify.php" method="post">
<?php echo recaptcha_get_html($publickey, $error); ?>
<input type="submit" value="submit" name="submit"/>
</form>