mugf umgf mguf gmuf ugmf gumf mufg umfg mfug fmug ufmg fumg mgfu gmfu mfgu fmgu gfmu fgmu ugfm gufm ufgm fugm gfum fgum
Note: these 'words' (valid or invalid) are all the permutations of the word mugf. These words are obtained by scrambling the letters in mugf.