[Typo3] espanding menu from standard template

[hdw]

Hello,
I'm new to typo 3 and i'm sure this question was already asked a 100 
times. I tried to understand TS and I'am about to understand the basics. 
I'm playing around to design a simple web-application and i succeeded 
using the static template 'BUSINIESS'. Now here's the question:
Is it possible to expand the 2-level menu coming from the static 
template to a 3-level menu, and if yes, how to do it.
I apreciate any help, and sorry for this kind of "simple" questions
regards
dieter