Код:
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php/$1 [L]
RewriteRule ^([^/]*)/([^/]*)/([^/]*)\.html$ /?page=$1&ext=$2&id=$3 [L]
</IfModule>