Bip39 how it works https://gravatar.com/sparklyusually6089a4f337 Despite the fact that it employs BIP32 method you may still import BIP39 seeds into Electrum wallet. Also besides BIp32 There's BIP44 Edition which some wallet use for the generation of seeds. For words that only have 3 letters, there isn't any 4th letter. By https://opensocialfactory.com/story24184432/keystone-bip39-the-smart-trick-of-bip39-wallet-that-no-one-is-discussing-https-dzen-ru-bip39-phrase-com