Common mistake
Treating neighbouring letter names as equal steps
It sounds like this
“C to D and E to F are the same size step — they're next to each other in the alphabet.”
Why it’s wrong
Letter names skip the black keys in some places and not in others, so the steps between them come in two sizes.
The lesson that fixes it
Cognosc spots mistakes like this.
When you explain something in your own words, Cognosc can tell exactly which mistake you’re making — not just that you’re wrong — and gives you a short lesson to fix that one thing.