For words that only have three letters, there is no 4th letter. For instance with the word “include”, there isn't any far more letters afterwards and so has to be the word "increase". The word “addict” is from the BIP39 wordlist however, you would've employed “addi” for “addict”. This extra https://ez-bookmarking.com/story18788284/not-known-facts-about-bip39-english-words