For words that have only 3 letters, there's no 4th letter. For example with the word “add”, there won't be any more letters Later on and so has to be the word "incorporate". The word “addict” is from the BIP39 wordlist but you would've applied “addi” for “addict”. - Lưu https://bookmarks-hit.com/story19855208/examine-this-report-on-bip39-mnemonic-phrase-tool