Don't open up an umbrella inside, and don't step on that crack or you'll break your back.
There's a whole host of strange superstitions across the world.
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Here in the UK, it's thought to be bad luck to see one magpie by itself.
Speaking of birds, in Egypt if you're the first person to spot an owl, that's bad luck too.
Over in Korea, it's thought you'll die by suffocation if you go to sleep with the fan on.
Got a crush on a girl? Never give her yellow flowers if you're in Russia. It's said to be a symbol of infidelity.
Be careful how you place your chopsticks - in Japan, sticking them straight up in a bowl of rice is thought to bring misfortune.
Think the sun is bad for you? Well, definitely don't go outside during a solar eclipse in India, apparently the sun's rays are toxic at that time.
Stick to singing around the piano, or not at all, and definitely don't sing at the dinner table in Holland - the Dutch believe you'll be singing to the devil.