parameters in crystal report

I know this is a stupid question but i searched all over internet but didnt find any explanation that helped me. I know there are already a few topics about passing parameter value to subreport but none of them helped me.

Ok so i have a main report called "Main1" than i have a subreport called "I" and in this subreport there is a parameter called "napis". So i want from vb.net 2005 runtime send a text so it would so in report (subreport area) in parameter.

So how to do it?!?

Thanks for the answers!