For words that only have three letters, there isn't any 4th letter. Such as with the word “incorporate”, there won't be any a lot more letters afterwards and thus should be the word "include". The word “addict” is while in the BIP39 wordlist however, you would have made use of https://digibookmarks.com/story18770774/how-much-you-need-to-expect-you-ll-pay-for-a-good-bip39-definition