multiple forms on single page

hi
I've been going trough some of the tutorials on asp.net and decided join two of the tutorials.
So I created a master page (menu.Master) containing a form and then derived a 'Web content form' from the master.
On content page I added a server side form within the 'ContentPlaceHolder' area and now get an error.
[HttpException (0x80004005): A page can have only one server-side Form tag.]


I guess i'm doing something fundamentally wrong, could someone explain how it should be done . Thanks
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