I speak both german and french, and I don't like being addressed with "Du" or "Tu", be it in letters, email or whatever. It is for me a lack of respect. In Fra

I speak both german and french, and I don't like being addressed with "Du" or "Tu", be it in letters, email or whatever. It is for me a lack of respect. In France the etiquette requires that you ask permission to use "Tu", and there are people who refuse you the right (it basically signals that they see you as a servant).