For words that only have 3 letters, there is not any 4th letter. As an example with the word “include”, there won't be any far more letters Later on and so need to be the word "insert". The word “addict” is within the BIP39 wordlist however , you would've employed https://hylistings.com/story19921324/the-basic-principles-of-bip39-passphrase-generator