Should Gaijins Speak Keigo (Polite Japanese)?
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If our Japanese is too elementary, surely no one will expect us to use keigo. "Namae wa nan'tte iuno?" will obviously be fine instead of "O-namae wa nan'tte iun desuka?" when asking for someone's name. But if our conversational skills are adequate enough to carry out even semi-intelligent dialogues, should we immediately switch to polite form if the other person is senior to you?