Bip39 protocol https://sergiouwfc622.fotosdefrases.com/exactly-how-to-generate-a-bip39-seed-a-step-by-step-guide 3a43fced052690635cc9fdce418514528b000dff3eaa5b986ea7be809062e775f2fe99c76733ff200b56fb70cac7c6ac7818b1e8139192a70fe274f5bf57fa46 For words that only have three letters, there isn't any 4th letter. For instance With all the word “include”, there aren't any a lot more letters... https://socialmediatotal.com/story5630258/electrum-import-bip39-5-tips-about-bip39-checksum-you-can-use-today-https-linktr-ee-bip39