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If your girlfriend wants to target Russian living in Russia, then you have to go for a .ru domain name and optimize the website thinking at Yandex as main search engine, even though Google is growing very fast right now in Russia too, especially thanks to Android Smartphones, which obviously have Google as main search engine. Here you have the Yandex guide for webmasters. The problem of a .ru domain is that - in Google - it is automatically geo-targeting Russia, so it would be impossible (or very hard) to have a subfolder like www.domain.ru/en/ being able to rank well in Google.com or Google.ca. For that reason, my suggestions is to create the English version using a generic domain. Regarding to your question about hosting the .ru domain in Russia or in the US, you could go for a third option: Hosting in the USA but with a Russian Ip. Finally, ranking in russian in Yandex is not all that easy as you may imagine