Add Sub Menus to HTML Page

I have a web page with a menu bar at the top of the page. Below the menu bar is an area for sub-menus to be displayed. When a user hovers over some of the menu items, there will be a list of links that show up in the sub-menu area. For other menu items, the sub-menu area will remain blank. I need someone who knows how to implement the JavaScript (or another method) to get it to work. I have attached the following: - an image of what each menu and sub-menu should look like - the HTML for the pages that you will build on - an Excel spreadsheet with a list of the submenus