Im trying to implement a menu in a wordpress theme,

HI,

Im trying to implement a menu in a wordpress theme, the main menu work fine without a submenu but it breaks down when i add submenu;. basically what am asking how do i show a parent menu along with its children menu.

Ex: Main menu
Menu1
menu2
etc..

here's what i have so far. this call the wp_nav_menu

if(has_nav_menu('primary-menu')){
                                    wp_nav_menu(array(
                                        'theme_location'  => 'primary-menu',
                                        'container'       => '',
                                        'container_class' => '',
                                        'container_id'    => '',
                                        'menu_class'      => ' ',
                                        'menu_id'         => '',
                                        'echo'            => true,
                                         'before'          => '',
                                        'after'           => '',
                                        'link_before'     => '',
                                        'link_after'      => '',
                                        'items_wrap'      => '<li class="dropdown">%3$s </li>',
                                        'depth'           => 0,
                                        'walker'          => ''
                                    ) );
                             }else {
                                        echo"Please click <a target=\"_blank\" href=".admin_url('nav-menus.php')."  > here </a> to create a menu";
                            }

and this at the bottom is my html template that i wish to implement the above menu with it, currently this html code below work fine in the html raw theme, just trying to use it in the wp_nav_menu

<li class="dropdown">
                                    <a href="index.html" class="dropdown-toggle">HOME<b class="caret"></b></a>
                                    <ul class="dropdown-menu">
                                        <li><a href="index.html">  (Shop)</a>
                                        </li>
                                        <li><a href="home-business.html">  (Business)</a>
                                        </li>
                                        <li><a href="home-slider.html">  (Slider)</a>
                                        </li>

                                    </ul>
                                </li>

Thanks in advanced.