My Irish grandmother loved crossword puzzles. She was very good at them too. I went through a period of time during which I tried very hard to be good at them, but alas, I am not. I found this distressing 25 years ago, but I got over it.
Tonight, I discovered that not being good at crossword puzzles is nothing compared with not understanding the concept of a crossword puzzle. It's silly, really, if you think about it. These puzzles are a Western invention, used for exercising the mind and having fun with trivia; a pass-time for lazy Sundays and/or cold evenings in the winter. They work well with the Latin alphabet even though words are not normally written in such a disjointed fashion - and never vertically.
While volunteering tonight I had a student who did not understand the concept of a crossword puzzle. Once I explained that only one letter goes in each box, we made enormous progress. I hadn't realized that this wasn't obvious.
If you think about it, why would it be obvious?