.htaccess rewriterule删除symfony2中的语言环境

Question

I need to remove locale from url in htaccess symfony2
for example:

site.de/de/....

to

site.de/....

symfony default htaccess looks like this:

DirectoryIndex app.php
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::\2$
    RewriteRule ^(.*) - [E=BASE:%1]
    RewriteCond %{ENV:REDIRECT_STATUS} ^$
    RewriteRule ^app\.php(/(.*)|$) %{ENV:BASE}/$2 [R=301,L]
    RewriteCond %{REQUEST_FILENAME} -f
    RewriteRule .? - [L]
    RewriteRule .? %{ENV:BASE}/app.php [L]
</IfModule>

<IfModule !mod_rewrite.c>
    <IfModule mod_alias.c>
        RedirectMatch 302 ^/$ /app.php/
    </IfModule>
</IfModule>

how can i remove locale in a safe way without breaking any routing.