问PHP插入不插入数据

EN

<?php
include 'db.php';

session_start();
?>
<!DOCTYPE html>

<html>

<head>

</head>
<?php 
include 'header.php';
?>

    <div id="logincontent"> 

    <div id="registerform" class="loginform-in">
        <h1>Registration</h1>
        <fieldset>
            <form id="myForm" action="registerscript.php" method="POST">
            Email: <input type="text" name="username"/><br />
            Password: <input type="password" name="pass"/><br />
            First Name: <input type="text" name="fname"/><br />
            Last Name: <input type="text" name="lname"/><br />
            Address 1: <input type="text" name="add1"/><br />
            Address 2: <input type="text" name="add2"/><br />
            Postcode: <input type="text" name="pcode"/><br />
            Telephone: <input type="text" name="phone"/><br />
            <button id="submit">Register</button>
            </form>

            <div id="ack"></div>
        </fieldset>
    </div>
    </div>
</body>
</html>

<?php
  include('db.php');

  $email = mysql_real_escape_string( $_POST["username"] );
  $pass = mysql_real_escape_string( md5($_POST["pass"]) );
  $firstname = mysql_real_escape_string( $_POST["fname"] );
  $surname = mysql_real_escape_string( $_POST["lname"] );
  $add1 = mysql_real_escape_string( $_POST["add1"] );
  $add2 = mysql_real_escape_string( $_POST["add2"] );
  $pcode = mysql_real_escape_string( $_POST["pcode"] );
  $phone = mysql_real_escape_string( $_POST["phone"] );

  if( empty($email) || empty($pass) )
  {
    echo "Email and Password are Mandatory";
    exit();
  }




$res = mysql_query("SELECT email FROM members WHERE email='$email'");
      $row = mysql_fetch_row($res);


  if( $row > 0 )
    echo "The Email $email has already been taken. Click Forgot Password to Retrieve";

  else
  {
      $sql = "INSERT INTO members (memberid, firstname, surname, address1, address2, postcode, telephone, email, password) VALUES (
                                       '',
                                       '$firstname', 
                                       '$surname', 
                                       '$add1', 
                                       '$add2', 
                                       '$pcode', 
                                       '$phone', 
                                       '$email'
                                       '$pass')";
   if( mysql_query($sql) )
     echo "Registration Successfull";
   else
     echo "An Error Occured Please Try Again";
}