Trezor One Bip39 Some words are shorter than 4 letters, including the word “act”. Other words are lengthier than four letters, including “abstract”. Be sure to make sure to allow recovery from mnemonic phrases that have invalid checksums (or that you don't have the wordlist) Remember to Have a look https://getsocialsource.com/story3922104/bip39-numbers-the-5-second-trick-for-bip39-word-list