Bip39 que es https://devinzryy552.trexgame.net/comprehending-bip32-vs-bip39-which-one-should-you-make-use-of Regardless that it makes use of BIP32 process you can still import BIP39 seeds into Electrum wallet. Also other than BIp32 There's BIP44 version which some wallet use for the technology of seeds. For words that have only 3 letters, there is not any 4th letter. https://myeasybookmarks.com/story6054517/bip39-rules-bip39-npm-no-further-a-mystery-https-t-me-bip39-chat