htaccess multiple parameters rewrite rule

I know this problem is over asked, but couldnt find anything fitting with my problem.

I'm currently creating a website, and my url are like :

www.foo.com/ or www.foo.com/index.php. They can take 1, 2 ,or three different parameters like

www.foo.com/index.php?page=Home&lang=en&article=1

What i'd like is an url like

   www.foo.com/Home/

or www.foo.com/en/Home

or www.foo.com/Article/1

or www.foo.com/en/Article/1

The page parameter is required, other two are not.. I cant have anything working for me... Any help would be greately appreciated

Thanks a lot !