Mod rewrite help

[abiao]

When people visit the pages in their folders, the folder won't show. for example:
When people visit www.domain.com/book/sell.php,
it will become www.domain.com/sell.html.

and www.domain.com/story/funning.php,
it will become: www.domain.com/funning.html

but www.domain.com/aboutus.php, it will be www.domain.com/about.html

Thanks.

[skylla]

could you provide the contents of .htaccess or any rewrite rules in the server config.