Subject: No German From You Unless It's Your Native Language, I'm English.
From: German_Sender@
Sender: German_Sender@

I append http://www.berklix.com/~jhs/std/no_german.txt
See also:
	http://www.berklix.com/~jhs/mail/no_german.html
	http://www.berklix.com/~jhs/std/no_german_bg.txt
	http://www.berklix.com/~jhs/std/not_a_german_customer.txt
	http://www.berklix.com/~jhs/std/why_not_more_german.txt
	http://www.berklix.com/~jhs/txt/grammar.html
& more generaly:
	http://www.berklix.com			Computer Consultancy
	http://www.berklix.com/~jhs/cv/		My Resume - English & German
	http://www.berklix.com/~jhs/contact/	Contact - German for business OK.
	http://www.berklix.com/free/		Free Software
	http://www.berklix.org			Free Organisations & Clubs

Thanks for your mail, 
I'm English, Please do Not write in German if that's not your first
language.  I can read German, but much prefer English. Unless you
are actually a native speaker of German, do not mail me in German !

I used to get too many Americans with German ancestry assuming I'm
German, & writing me in half baked German ! My German grammar is
also half baked (though I have a Large german vocabulary), & real
German grammar is bad enough, so it would be foolish to lead each
other astray, puzzling about & worse, even learning each other's
faulty grammar, so Please do not mail me in German unless you Are
German (or Austrian or Swiss)

- Some people write to me in German because they see a .de in a
  domain, or mention of Munich/ Muenchen etc, even though all my
  prior mail discussion has been in English on international mail
  lists.  Wrong deduction ! I'm not German !  I am English.
- Perhaps people are being friendly or helpful or practising their
  German on me, learnt at school, or with USA German ancestry etc, but ...
- Though my German is good enough for me to read real German, it is easily
  confused, & I really don't want to wade through unsolicited-
  switched- to- quasi- maybe- German, when I must both try to
  understand the meaning, and simultaneously guess if (A) this is
  _proper_ German where I should learn the grammar, or (B) this is
  junk quasi German from a non native German speaker, with perhaps
  as many but different mistakes as I make, where learning the
  sender's grammar could degrade my German grammar.

Exceptions
  Unless there's someone on CC: who can't read (not can't write) English.
  Unless you're quoting or preparing a German text or publication.

PS
If you first language is French you could also write short notes in 
simple French, but Not unless you are a native French speaker.