Parse error: syntax error, unexpected '$action' (T_VARIABLE) in C:\xampp\htdocs\ajax.php o

How to fix this, please help me.

<?php
$conn = mysqli_connect("127.0.0.1", "root", "");
mysqli_select_db ( $GLOBALS [ 'test' ] , $db ) 

$action = $_GET['action'];
switch ($action) {
    case 'ajax_check_user':
        $txtuser = $_POST['txtuser'];
        $query = "SELECT * FROM tbl_user WHERE user_name='".$txtuser."'";
        $result = mysqli_query($query);
        if(mysqli_num_rows($result) > 0){
            echo json_encode(TRUE);
        }else{
            echo json_encode(FALSE);
        }
        break;
    case 'ajax_check_pass':
        $txtuser = $_POST['txtuser'];
        $txtpass = $_POST['txtpass'];
        $query = "SELECT * FROM tbl_user WHERE user_name='".$txtuser."' AND user_password=MD5('".$txtpass."')";
        $result = mysqli_query($query);
        if(mysqlii_num_rows($result) > 0){
            echo json_encode(TRUE);
        }else{
            echo json_encode(FALSE);
        }
        break;
    case 'ajax_login':
        $txtuser = $_POST['txtuser'];
        $txtpass = $_POST['txtpass'];
        $query = "SELECT * FROM tbl_user WHERE user_name='".$txtuser."' AND user_password=MD5('".$txtpass."')";
        $result = mysqli_query($query);
        if(mysqli_num_rows($result) > 0){
            echo "TRUE";
        }else{
            echo "FALSE";
        }
        break;
    case 'ajax_check_user_register':
        $txtuser = $_POST['txtuser'];
        $query = "SELECT * FROM tbl_user WHERE user_name='".$txtuser."'";
        $result = mysqli_query($query);
        if(mysqli_num_rows($result) > 0){
            echo json_encode(FALSE);
        }else{
            echo json_encode(TRUE);
        }
        break;
    case 'ajax_register':
        $query = "INSERT INTO `tbl_user` (`user_id`, `user_name`, `user_password`, `user_email`, `user_phone`) VALUES (NULL, '".$_POST['txtuser']."', MD5('".$_POST['txtpass']."'), '".$_POST['txtemail']."', '".$_POST['txtphone']."');";
        mysqli_query($query);
        if(mysqli_insert_id() > 0){
            echo "TRUE";
        }else{
            echo "FALSE";
        }
        break;
    default:
        # code...
        break;
}
?>

Parse error: syntax error, unexpected '$action' (T_VARIABLE) in C:\xampp\htdocs\ajax.php on line 5