For words that only have three letters, there isn't a 4th letter. Such as with the word “include”, there isn't any more letters afterwards and therefore has to be the word "include". The word “addict” is from the BIP39 wordlist however you might have made use of “addi” for “addict”. https://atozbookmarkc.com/story19233617/bip39-phrase-generator-can-be-fun-for-anyone