For words that only have three letters, there is not any 4th letter. By way of example with the word “incorporate”, there isn't any far more letters afterwards and thus should be the word "add". The word “addict” is during the BIP39 wordlist however, you would've applied “addi” for “addict”. https://bookmarkahref.com/story18814673/examine-this-report-on-bip39-passphrase