Sub menus are not being displayed under main menu

hello!
I recentrly add new pages to my site and wanted to have these new pages under the main page as a dropdown control. I do the necessary process (because this is not the first time i do it) but when i click on the menu, the sub menus are not displayed under it.

I wonder if there is an optoin to enable submenus or something like that.

btw i am using mana theme on my wordpress site.

Thanks everyone in advanced. Here is my site: http://c51.444.myftpupload.com/
there should be a dropdown submenus under SPEAKING page