For words that have only three letters, there is absolutely no 4th letter. For instance with the word “include”, there isn't any far more letters afterwards and thus need to be the word "include". The word “addict” is inside the BIP39 wordlist however you would've employed “addi” for “addict”. Tips https://maximusbookmarks.com/story18974726/a-review-of-bip39-phrase-list