For words that have only 3 letters, there isn't any 4th letter. Such as with the word “insert”, there won't be any more letters afterwards and thus should be the word "incorporate". The word “addict” is inside the BIP39 wordlist but you might have applied “addi” for “addict”. BIP39 and https://freebookmarkpost.com/story18903307/top-latest-five-bip39-words-urban-news