htaccess从重写中排除文件夹？

I currently almost have what I need but missing one important part.

I have a htaccess rewrite to change the .php extension to /

I figured out a way to exclude some files, but now I need the ability to exclude a few folders

This is what I have..

RewriteEngine On

## don't touch /folder URIs
RewriteRule ^snippets/ - [L,NC]
RewriteRule ^admin/ - [L,NC]
RewriteRule ^emails/ - [L,NC]

# hide .php extension snippet
# To externally redirect /dir/foo.php to /dir/foo
RewriteCond %{THE_REQUEST} !/(confirm-ticket|account-profile)\.php [NC]
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s([^.]+)\.php [NC]
RewriteRule ^ %1/ [R,L]

# To internally forward /dir/foo to /dir/foo.php
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.+?)/?$ $1.php [L]

I am pretty sure the don't touch /folder URIs section is wrong, as those are the folders i am trying to exclude from the rewrite... help?

Thanks, -O