For words that have only three letters, there is no 4th letter. For example with the word “incorporate”, there aren't any much more letters Later on and therefore should be the word "add". The word “addict” is in the BIP39 wordlist however you would've utilised “addi” for “addict”. Keep your http://collinmmss433.lucialpiazzale.com/opening-the-power-of-bip39-a-comprehensive-check-out-word-lists-and-secure-pocketbooks