How to properly set up a multilingual site on the language directories /ru, /en, /gr?

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evgensupermen2015-09-30 11:30:45

Search Engine Optimization

evgensupermen, 2015-09-30 11:30:45

Good afternoon. I have the following question:
I am creating a multilingual project.
I make language versions of the site on the directories /ru, /en, /gr, etc.
For the next year, only the version of the site with the directory /ru, i.e. the Russian version, is relevant. So far, only the Russian-language version has been implemented. Other language versions will be relevant in a year (there are none at all yet).
The question is how to set everything up correctly in such a situation so that there are no problems with indexing and there are no problems with search engines?
Which domain should be specified as the main one in host: Site.org or Site.org/ru?
Is it right that Site.org now has a 302 redirect to Site.org/ru.
What to do and how to implement Site.org/en, Site.org/gr
How to properly set up all the technical nuances so that there are no problems with SEO?