I used to believe that knock knock jokes were always funny and you could make them up out of any words. My favourite that I made up was:
Knock Knock
(who's there?)
door handle
(door handle who?)
Cat.

TS

When I was little, I used to get the words 'terrorist' and 'tourist' confused - so I used to think that tourists travelled around the world killing people.

Niki

I used to think that risque was just another way of saying risky.

Anon

I was having a conversation with my grandma one day, about history and things she historical events she lived through and whatnot, and she told me she was in a class (she was about 14) after JFK was shot and she couldn't understand why everyone was upset. She thought "assassinated" meant to win an award or was an honor.

Kayla

My father is a paramedic so one day after work when I was about 6 yrs old, he said today I had a patient with his bone sticking out of his leg. Earlier that week I heard someone say boner, and though thats what it meant. So I said , like a boner? lol he didnt talk to me for a while

TaNeal

When I was about 4 my neighbor would say "Peas" every time we said goodbye, I picked up on it and began saying "peas" to all my friends. My mother told me (after my neighbor moved away) that he was in fact saying "peace." D'oh

x-lax

I thought 'infrared' was the past of 'to infrare'.

Lloyd B

When I was little I used to think that when people in movies would draw their swords and say "On guard", they were saying "I'm God". So whenever I play with someone and I'd pretend to draw my sword I'd shout "I'm God!".

Anonymous

I'm from Ireland and in primary school coming up to St. Patricks Day they'd have plays and stuff on in scool and they'd always mention the millions of people who emigrated, but i thought emigrated meant disintegrated at the time so could never understand how millions of people went puff into dust... i pictured it kinda like vampires getting staked in Buffy... but Buffy wasn't on tv then so blame over active imagination....

nicola

I used to believe that a "grilled cheese sandwich" was a "girl cheese sandwich" and would refuse them and demand a "boy cheese sandwich". I was a sexist little kid.

Johnny

I used to think testers were short for testacles! So in the shop i used to say can i try a testacle!

Ro

When I heard the phrase "there's no rest for the wicked" when I was very young, I thought that it meant that wicked people get very little rest because there are so many wicked things that need doing. I believed that for many years.

the evil microwizard

when i was little i used to think that an appetizer was called lingerie, and that lingerie was an appetizer, so once i saw my mom maken like shrimps, and dips and such and i was like: "mom nice lingerie!"

Christina L.

When I was younger I loved potpouri. But I always confused potpouri with diarhea, so I would go around stores chanting, "Diarhea! Diarhea!" because I always got excited when I saw a bag of potpouri. (I think I thought this because I pronounced potpouri as poperia, so it sounded like diarhea to me! And to this day I still pronounce it as poperia.)

Azalee

When I was in kindergarten to third grade, I used to believe that scientific-sounding words were grownup words and that I shouldn't say them. I would try to avoid saying words like "atmosphere," "digestion," "photosynthesis," "abdominal," etc., and if I did have to say them, I got really embarrassed. I was even embarrassed by the song "Let's Go Fly A Kite" in Mary Poppins because it had the line "Up through the atmosphere, up where the air is clear."

Rachel

When i was a kid, i asked my grandfather how the heat in our house worked. He showed me the baseboard heater in the kitchen and said something that i heard as "the heating elephants inside". Eventually i found out he was saying "elements" but for a long time i had imagined little tiny elephants walking around inside the heater to make it warm. i spent about an hour that day sitting next to the heater trying to look inside it and see the elephants.

Anon

My mom was hosting a fundraiser one year, but I thought she was saying "fun razor". I wanted one (a fun razor)so badly because my dad would never let me play with his razors.

papa2be

Whenever me or my brothers were getting told off, my mum would say "if you do that again you will get a good hiding!" When she said it I pictured myself actually hiding in the wardrobe or another good hiding place

michelle

I used to think that babies could communicate with eachother, just as adults communicate with eachother. I just assumed there was "baby's English" and then "adult English". I also theorized that if you were at JUST the right age, (for example: 3 year, 7 months and two days old) you would be able to speak both languages.

At the time, I had a cousin who was 3 years old and her brother was just a baby. Me and my cousins all believed in my theory. We sought to exploit my 3-year old cousin and create a "baby translation company". :)

Moose

My fianace grew up around his father and cars and always talking about them, looking at them, etc. One night I noticed that he was using the word "deluxe" in the wrong context, and asked him what he thought it meant. When he responded that it mean "bad" or "worse then the rest" i was baffled that he had the exact opposite meaning of what it really meant. I asked him why he thought that. He said that because in cars the "deluxe" version is always the worse of the models. You have stuff like "supreme" and all the super decked out models. Than the base model they still call something nice like "deluxe" even though it's the bottom model. So he thought it meant crappy version.

Anon