You should try "The Crocodile Dundee" method of telling the sex when talking to someone!!!For English speakers, however, such a problem apparently matters less. Therefore, they communicate in a way that is different from ours. They start to chat with a preset idea that they do not know their new counterparts' sexes like we do not know about ages of new people who we start to chat with. So there's a behaviour pattern that can seem weird for us, but might be guite fine for English speakers. And I want to learn it.