For words that have only 3 letters, there isn't any 4th letter. By way of example with the word “add”, there isn't any much more letters afterwards and so should be the word "add". The word “addict” is during the BIP39 wordlist however , you would have employed “addi” for https://bookmark-search.com/story19368279/the-ultimate-guide-to-bip39-seed-phrase-mnemonics-generator