For words that have only three letters, there isn't a 4th letter. For example with the word “include”, there isn't any far more letters afterwards and thus have to be the word "increase". The word “addict” is inside the BIP39 wordlist however, you might have utilized “addi” for “addict”. A https://socialbaskets.com/story4726215/fascination-about-bip39-english-words