RewriteEngine on
RewriteRule ^([a-z]+)-([a-z]+)-([0-9a-z_]*)-?(.*)$ $1-$4?$2=$3 [NC,QSA]
RewriteRule ^([a-z]+)-?\.html$ $1.php [NC,L,QSA]

А если ещё и кодировка не кодировка, то так

php_flag session.use_trans_sid off
php_flag session.use_only_cookies on
php_value default_charset windows-1251

RewriteEngine on
RewriteRule ^([a-z]+)-([a-z]+)-([0-9a-z_]*)-?(.*)$ $1-$4?$2=$3 [NC,QSA]
RewriteRule ^([a-z]+)-?\.html$ $1.php [NC,L,QSA]