For words that have only three letters, there is not any 4th letter. Such as with the word “include”, there isn't any much more letters Later on and therefore has to be the word "include". The word “addict” is in the BIP39 wordlist however , you would've applied “addi” for https://socialicus.com/story4912906/a-secret-weapon-for-bip39-words-to-numbers