I read some tutorials about mod rewrite, but I can't find what I'm looking for. I want only one RewriteRule for all my URI's that is doing the following:

* I want that the '-' is replaced by '\_'. So if i have example.com/page-hello is should be rewriten to example.com/page\_hello
* Each url should be replaced with .php behind it. So if i have example.com/page, is should be rewriten to example.com/page.php

So my question is, how to make this happen?