When I was a kid, a newspaper published the Russian Alphabet. I thought I was very clever in substituting the letters of English words with the Russian equivalent.... to this day, I blush when I am reminded of it, as I told everyone I could now speak/write Russian!
A childhood belief about foreign languages

others believed things like this
- I thought all you had to do to speak Russian was add -ski to the end of every word!— nateski
- I used to think that Russian was just English backwards— Millie
- that the bears which live in the cracks between paving stones are Russian— jonah fonder
- I used to believe there was a Russian Leader named Garbage Trough and an Arabian named Are A FatAnon
- I used to believe, that I am able to speak every foreign language only by learning "their" alphabet.— matej
- I used to think everyone in the world knew and thought in English, but choose to speak different languages. Anon