The main reason we confuse these three words is because they are homophones. They sound the same, so our overloaded minds mash them together into one word: to. It makes grammarians want to scream — two times!
- You’re to funny.
- We were going two buy some more popcorn today.
- They like cake so they bought too of them.
Everyone uses these words correctly in speech because they sound the same. The preposition to is used to indicate that one is moving “for the purpose of” or “in the direction of.” We were going to buy some popcorn; my cat is going to the window. Too means “in excess” or “also.” I ate too many cookies this year and he did, too.
Anything involving two uses tw somewhere in the word: between, twice, twins, twenty, intertwine, and more.