Today I received our first telemarketer call in Switzerland. I speak just enough German to know that is why he was calling. Plus, the tone of voice for telemarketers seems to be the same worldwide despite the language and accent. An annoyingly cheerful blast of words that allows for no polite interruption.
Using the broadest American accent I could muster, I interrupted his spiel with "Ich verstehe Deutsch nicht. Verstehen Sie Englisch?"
Then he replied "Nein. Guten Tag." Click.
Wow! What an easy way to end a conversation that would likely have been an insistent sales pitch otherwise. It's also the first time a telemarketer has hung up on me instead of the other way round.
I believe that even when I am more comfortable with German I will continue to use that line with telemarketers.