For words that only have 3 letters, there isn't a 4th letter. For instance with the word “increase”, there isn't any far more letters Later on and therefore has to be the word "increase". The word “addict” is while in the BIP39 wordlist however, you would have made use of https://agendabookmarks.com/story18756440/not-known-factual-statements-about-bip39-explained