Longest officially recognized place name is Taumatawhakatangihangakoauauotamateapokaiwhenuakitanatahu.
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If you mouth the word "colorful" to someone, it looks like you are saying "I love you".
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The word "listen" contains the same letters as "silent."
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The word "impossible" dropped in use by 50% over the course of the 20th century
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Switching letters is called spoonerism. For example, saying "jag of Flapan", instead of "flag of Japan".
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