A couple of years ago, as I was just starting to study Japanese, I had a language exchange partner with whom I would meet at a cafe once a week. His level of English was much higher than my level of Japanese so, of course, we spent most of the time speaking in English.
One of the things he told me about were these Japanese phrases which could be used by Japanese people who spoke little to no English. The way it worked was that if the Japanese person said a certain thing in Japanese, it sounded the same as another, different sentence in English. I don’t think they were really used often by the Japanese, but were more like jokes, or maybe mnemonics to remember the correct English phrases. Unfortunately, I cannot remember any of the examples since my Japanese was at such a low level when I first heard them.
I only know of one example, but in the other direction. If an English speaker is in Japan and wants to say “don’t mention it” or “you’re welcome”, he can simply say “Don’t touch my mustache” which, I guess, sounds somewhat like どういたしまして.
Does anyone know what I am talking about? If so, do you have any examples?