For words that only have 3 letters, there's no 4th letter. As an example with the word “incorporate”, there won't be any a lot more letters afterwards and thus should be the word "increase". The word “addict” is in the BIP39 wordlist but you would've employed “addi” for “addict”. Shop https://bookmarkbirth.com/story18851032/not-known-facts-about-bip39-english-words