Within Google Search Console, there are several options for handling querystring parameters. One of the options on these is making a language indicator.
To date, I always thought that this would be the best means of providing multilanguage support to a website so that Google could distinguish which pages were developed for what language. It appears I’m wrong, though, after our SEO analyst, Nikhil Raj, found this little side note in a recent Google video on parameters.
The best practice is to place languages in subdirectory or subfolder rather than parameter to help search engines more easily understand site structure.
At 11:35 in the video below, Maile Ohye makes the recommendation (not a requirement).
With that in mind, if you have a WordPress site, check out WPML – a comprehensive Multi-language WordPress integration with the following features:
- Multilingual content
- Comments translation
- Standard translation controls
- Automatic ID adjust
- Browser language detection
- Translation management
- Theme and plugins localization
- CMS navigation
- Sticky links
Thanks Doug for the mention! The best option for multilingual websites is to use canonical tag in conjunction with alternate link tag
See http://support.google.com/webmasters/bin/answer.py?hl=en&answer=189077