Options +FollowSymLinks
RewriteEngine On

RewriteRule a-(.+).html articles.php?keyword=$1
RewriteRule v-(.+).html videos.php?keyword=$1
RewriteRule b-(.+).html blogs.php?keyword=$1
RewriteRule n-(.+).html news.php?keyword=$1
RewriteRule c-(.+).html contact.php?keyword=$1
RewriteRule s-(.+).html sitemap.php?keyword=$1
RewriteRule p-(.+).html privacy.php?keyword=$1

RewriteRule (.+).html index.php?keyword=$1