http://www.example.com/vb/forum-id-forum-title/
http://www.example.com/vb/forum-25-منتدى-تطوير-المواقع-و-المنتديات
forum-name/threadid-threadname.html
RewriteEngine onRewriteRule [^/]+/([0-9]+)-[^/]+\.html http://www.example.com/vb/showthread.php?t=$1 [L,R=301]
forum-name/threadname-threadid.html
RewriteEngine onRewriteRule [^/]+/[^/]+-([0-9]+)\.html http://www.example.com/vb/showthread.php?t=$1 [L,R=301]
forum-name/threadname-threadid/
RewriteEngine onRewriteRule [^/]+/[^/]+-([0-9]+)/ http://www.domain.com/vb/showthread.php?t=$1 [L,R=301]