For words that have only 3 letters, there is not any 4th letter. For instance with the word “include”, there isn't any additional letters Later on and thus must be the word "include". The word “addict” is from the BIP39 wordlist however, you would've made use of “addi” for “addict”. https://social-galaxy.com/story4257910/considerations-to-know-about-bip39-seed-phrase-generator