Words that mean something different than what I thought they meant

A work in progress personal but incorrect etymology?

A forethought: When I was young, from about the age of seven to twelve or so, I had a wonderful english tutor named Melissa. At the age of seven I had moved from Uruguay to the States and knew virtually zero english. Perhaps I knew how to say hello? Not sure. Either way, Melissa employed many techniques to help me learn, and while starting up this list I have remembered a good one! When I would encounter a word that was not in my vocabulary and I would ask what this meant, she would often respond with the question, what did I think it meant. Super simple but often times when we would discuss what I thought it might mean I got it right. Felt pretty good, I felt smart and affirmed and I am grateful for Melissa for teaching me in such a thoughtful manner. (side note: as i wrote this I discovered grateful is NOT spelled greatful) However, this list is basically me listing all the times I employed this method and have not reaped correct results! Alas learning is forever…!

Formidable

What I thought it: able to form something, like a metal that is malleable

What is actually means: inspiring fear or respect through being impressively large, powerful, intense or capable

Why: I split the word up into “form” — a shape and midable — able to do something… so able to shape came to mind