Here I try to rewrite the parameters in .htaccess and make the last parameter optional:

RewriteRule ^produktas/([0-9a-zA-Z_-]+)/?([0-9a-zA-Z_-]+) /produktas?slug=&var= [NC,L]

So if I type http://site.lt/produktas/the-glass, then I want to actually get http://site.lt/produktas?slug= the -glass, but the second parameter var I want to be empty. But when I run it, I get the first parameter and my $_GET variable looks like this:

Array ( [slug] => the-glas [var] => s )

If I only enter one parameter, how can I make the first parameter full and the second parameter empty: http://site.lt/produktas/the-glass?