Surely everyone has a list of these? Off the top of my head, the first one I can think of involves my poor education....
When I was a young teenager, I had a huuuge crush on a girl, and I think it's true to say she was extremely attractive. I'd made various excuses to successfully walk with her as she walked home from school. Fortunately it was on my way home, and regardless of the fact I had a bicycle and could have cycled home in a fraction of the time, I weebled my way in to walking and talking with her (which, as a rather insecure teenager is pretty good). This went on for quite a time, and true to my social ineptness, I just couldn't work out what to do or how to take the "next step" of attempting to form a relationship....
So, one day, I made my mind up. "Simple" I thought. "I'll just come out with it!". So just as we were about to reach her home, I managed to blurt out in awkwardteenagese a stammering "I really like you". She stopped, turned towards me, and our eyes locked together. Looking directly into my eyes with her deep blue eyes, she then shook her tousled blonde curly hair, and purred back the unforgettable words of "the feeling is mutual".
Now, at this point, you'd think things were going pretty well. And they should have been, except for one thing: I had no idea what the word "mutual" meant. I was a bit puzzled, and it was then my brain made the very worst deduction it could possibly ever make in my teenagehood: it equated the word "mutual" with the word "mutant" thus forming a perfect cringeworthy moment. "Oh" I said, feeling very crestfallen and rejected. I said "OK then", and promptly hopped on my bike and cycled off as quickly as I could. I never walked with her after that.
Eventually I did bother to use a dictionary and was devastated (trust me as male teenager I was really absolutely devastated) to find out what "mutual" meant (I blame Comprehensive school education). But by then, I was too embarrassed. Looking back on it now, I do chuckle and wonder what the heck she thought of me. Perhaps taking "playing hard to get" a bit too far? On the positive side, I've never, ever forgotten the meaning of the word "mutual". Ever.