Second menu underneath the primary

Hey Guys

i inserted a new menu on the bottom of the header but i wil be shown left of the main menu. How do i get it underneath the primary menu ?

This is the css of the secondary menu

001
	#main-nav   {
002
	    height: 30px; /* set to the height you want your menu to be */
003
	    margin: 0 0 10px; /* just to give some spacing */
004
	}
005
	#main-nav ul    {
006
	    margin: 0; padding: 0; /* only needed if you have not done a CSS reset */
007
	}
008
	#main-nav li    {
009
	    display: block;
010
	    float: left;
011
	    line-height: 30px; /* this should be the same as your #main-nav height */
012
	    height: 30px; /* this should be the same as your #main-nav height */
013
	    margin: 0; padding: 0; /* only needed if you don't have a reset */
014
	    position: relative; /* this is needed in order to position sub menus */
015
	}
016
	#main-nav li a  {
017
	    display: block;
018
	    height: 30px;
019
	    line-height: 30px;
020
	    padding: 0 15px;
021
	}
022
	#main-nav .current-menu-item a, #main-nav .current_page_item a, #main-nav a:hover {
023
	    color: #000;
024
	    background: #ccc;
025
	}