I've posted here about differences between UK and US English, but just because I've studied up on the topic doesn't mean I always remember my lessons.
A few days, while chatting with a Welsh woman at my university, I said to her, "I like your pants! They're quite nice!"
Well, naturally, she looked pretty shocked. I had forgotten that "pants" in UK English refers to underwear. She looked down, to make sure her underwear wasn't showing, and then she burst into laughter and said, "You mean my trousers, right?" We had a laugh then about my mistake and about UK versus US English.
It was a good reminder that translation doesn't always occur between two distinct languages; it can also take place between two versions or dialects or registers of the same tongue.
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