laufs alufs luafs ulafs aulfs ualfs lafus alfus lfaus flaus aflus falus lufas ulfas lfuas fluas uflas fulas aufls uafls afuls fauls ufals fuals lausf alusf luasf ulasf aulsf ualsf lasuf alsuf lsauf slauf asluf saluf lusaf ulsaf lsuaf sluaf uslaf sulaf auslf uaslf asulf saulf usalf sualf lafsu alfsu lfasu flasu aflsu falsu lasfu alsfu lsafu slafu aslfu salfu lfsau flsau lsfau slfau fslau sflau afslu faslu asflu saflu fsalu sfalu lufsa ulfsa lfusa flusa uflsa fulsa lusfa ulsfa lsufa slufa uslfa sulfa lfsua flsua lsfua slfua fslua sflua ufsla fusla usfla sufla fsula sfula aufsl uafsl afusl fausl ufasl fuasl ausfl uasfl asufl saufl usafl suafl afsul fasul asful saful fsaul sfaul ufsal fusal usfal sufal fsual sfual
Note: these 'words' (valid or invalid) are all the permutations of the word laufs. These words are obtained by scrambling the letters in laufs.