For words that have only three letters, there isn't any 4th letter. Such as with the word “include”, there aren't any more letters Later on and so has to be the word "include". The word “addict” is inside the BIP39 wordlist but you might have employed “addi” for “addict”. In https://socialmarkz.com/story9283504/top-latest-five-bip39-words-urban-news