Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Many believe that if all of the candles on a birthday cake are blown out with one breath, while making a silent wish, the wish will come true.
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It is bad luck to put new shoes on a bed (or a table) (comes from the tradition of dressing a corpse in new clothes and shoes and laying them out so everyone can give their respects) - (UK)
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An acorn at the window will keep lightning out
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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Before traveling a person should, apparently, sit on their luggage. (Russian)
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Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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In Asia, the digit 4 never appears in any Nokia handset model number, because 4 is considered unlucky in many parts of Southeast/East Asia.
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