For words that have only 3 letters, there isn't any 4th letter. By way of example with the word “insert”, there are no extra letters afterwards and therefore has to be the word "include". The word “addict” is within the BIP39 wordlist however , you would have employed “addi” for https://peakbookmarks.com/story18911607/considerations-to-know-about-bip39-word-list-pdf