Complete htaccess code for remove file extension + add a trailing slash like wordpress

.htaccess

<IfModule mod_rewrite.c>
RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ $1.php
#RewriteRule ^([a-z]+)\/?$ $1.php [NC]


RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.html -f
RewriteRule ^(.*)$ $1.html
#RewriteRule ^([a-z]+)\/?$ $1.html [NC]

</IfModule>