For words that only have three letters, there isn't any 4th letter. For instance with the word “incorporate”, there aren't any far more letters Later on and so have to be the word "incorporate". The word “addict” is in the BIP39 wordlist however , you might have made use of https://bookmarkplaces.com/story18799077/how-much-you-need-to-expect-you-ll-pay-for-a-good-valid-bip39-seed-phrase