Years ago, there was a famous deli in New York. The owner had a big heart and frequently hired refugees from other countries.
One day, a new patron came in and was waited on by a young man from Thailand, who conversed in perfect Yiddish. The customer was so impressed, he found the owner.
"I'm very impressed with your waiter, but where'd he learn Yiddish?" he asked the owner.
"Shhh" the owner replied. "He thinks I'm teaching him English!"
Translator
These jokes are of an unknown origin. Feel free to submit corrections or add to the list. I will edit when possible, to improve the flow and correct errors.