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I just found myself in situation that I am telling about someone who added to me in Skype: because of the nickname I think that it is a girl and used all the time the word «she». But as she didn't say anything yet with exception the "hey :)", I can't even be sure it is a human (it is could be just a bot). So I am afraid that talking about her by using «she» could lead to misunderstanding. Shall I use the word «it»? Or is it wrong? Is there another way?
E.g. in Russian a sex have any noun, so I can say «she» and mean «the person» because the «person» have feminine gender. Either I can say «he», and mean «the one», because it is male gender. So, this way I don't confuse my interlocutor about my knowledge about a person's sex.