In some of the days I spent at ACU, I taught English in Academic Advance. AA is a program set up to help those students who did not do well on entrance tests. Many of the students I had were foreign students. Although they spoke English very well, they did not "get" idioms and other fine points of the language. For example, the verb "to be" just didn't make sense to them. They wrote in very long sentences linked with many "ands". Paragraphs were unheard of in their essays.
My Bas Blue catalog advertises a book called Here Speeching American: A Very Strange Guide to English as it Garbled around the World. Examples from actual signs, menus, advertisements and brochures are used. Some from the review:
Keep all fours in the bus--eyes only out window. (Mexican bus)
Compulsory Buffet Breakfast (Melia Hanoi Hotel, Vietnam)
Foot wearing prohibited (Buddhist temple, Burma)
Go Away (Barcelona travel agency window)
Swimming is forbidden in the absence of the savior. (Hotel swimming pool, France)
I wish I had this book for my class. It would have been fun to have my students decipher the mistakes. I must add too that I would be woefully inadequate if I had to speak any other language but English.