When I was about 6 I was in the back garden and my Mum tripped over, I laughed and said 'Your such a twat', my mum belted
me for that and I didn't understand why at the time.
I thought Twit and Twat meant the same thing.
A childhood belief about swearing

others believed things like this
- There was a custard well in my back gardenAnon
- I thought a "fallen soldier" was one who'd tripped and fallen during a battle.Anon
- I thought that exorcise and exercise both meant the same thing— Dobby Bob
- I thought the phrase "At one's disposal" meant you should dispose of the person or thing.— Geirskogul
- I thought “guerrilla tactics” meant fighting like a gorilla— beating your chest and that sort of thing.— Kai
- The first time I hear about a serial killer, I laughed. You can't kill cereal. It's not alive.Anon