For words that have only three letters, there is no 4th letter. Such as with the word “include”, there isn't any a lot more letters afterwards and thus has to be the word "incorporate". The word “addict” is from the BIP39 wordlist however you would have utilized “addi” for “addict”. https://friendlybookmark.com/story19502448/top-latest-five-bip39-words-urban-news