sunnb usnnb snunb nsunb unsnb nusnb sunnb usnnb snunb nsunb unsnb nusnb snnub nsnub snnub nsnub nnsub nnsub unnsb nunsb unnsb nunsb nnusb nnusb sunbn usnbn snubn nsubn unsbn nusbn subnn usbnn sbunn bsunn ubsnn busnn snbun nsbun sbnun bsnun nbsun bnsun unbsn nubsn ubnsn bunsn nbusn bnusn sunbn usnbn snubn nsubn unsbn nusbn subnn usbnn sbunn bsunn ubsnn busnn snbun nsbun sbnun bsnun nbsun bnsun unbsn nubsn ubnsn bunsn nbusn bnusn snnbu nsnbu snnbu nsnbu nnsbu nnsbu snbnu nsbnu sbnnu bsnnu nbsnu bnsnu snbnu nsbnu sbnnu bsnnu nbsnu bnsnu nnbsu nnbsu nbnsu bnnsu nbnsu bnnsu unnbs nunbs unnbs nunbs nnubs nnubs unbns nubns ubnns bunns nbuns bnuns unbns nubns ubnns bunns nbuns bnuns nnbus nnbus nbnus bnnus nbnus bnnus
Note: these 'words' (valid or invalid) are all the permutations of the word sunnb. These words are obtained by scrambling the letters in sunnb.