I dreamt that I was talking with a man about my age who came from Sweden to the States in his youth. I remember noticing that he had a bit of an accent. He told me that he had been losing his Swedish over the years, though. And then he told me that he had once been at a lecture where some brain scientist had argued that remembering swears and other funny words in your mother tongue helped keep it in good shape. As he was saying this, he mumbled something in Swedish and burst out laughing. Apparently, such words have many connections in the brain, and thus they help you keep the language. When I woke up, I remembered that I had spent many years in the States and England with few opportunities to practice my mother tongue. My dream may well offer a plausible reason why I have developed a predilection for swearing in that language.