Language Code In URL adds language code so http://example.com/some-url will become http://example.com/en/some-url for english and http://example.com/de/some-url for german. Language code will be automatically set according to language code in URL, so you can post links to specific language mutation of your store.

Note: You dont have to use seo URLs, but .htaccess has to be set!

Demo:
http://oc154.opencartex.com/