bbbb bbbs bblb bbls bffl bffs bfts bftt blbt blls blob bloo blot blss blst blts bobb bobo bobs boff bofs boll bolo bols bolt boob boof bool boos boot boso boss bost botb boto bots bott bsff bsfs bsos bsts btob btss bttb ffff ffss fftf flob floo flos flot flts fobs fobt fofo foll folo fols folt foof fool foos foot fosb foso foss fost foto fots fott fsfo fssf ft-l ftlb ftos lbos lfts llbs llll lloo lob- lobb lobo lobs loff loft loll lolo lols loob loof lool loos loot loso loss lost lotl loto lots lott lsof lsso lsts ltbf ltbl obbo obls obol obos obot obss obst obts off- offo offs ofst olbo olfs ollo olof olos olot olst ooff oofs oolo oooo ooos oost ootb oots oslo osoo osos ossb osso osts otbs oto- otof otoo otos otso otto otts s-os sbbs sbot sbst sfls sfos sfss sfts slft slob sloo slos slot slst slts sobo sobs sobt sofo soft solf soll solo sols solt soof sool soos soot soso soss sost sotl soto sots ssfl sslt ssot sssb sssf ssss sstb sstl ssts stbs stlo stlt stob stof stol stoo stos stot stsf stss tbbs tbst tfot tfss tlos tobo tobs tobt toff tofo toft tol- toll tolo tolt toof tool toos toot tosb toso toss tost toto tots tott tsfl tsob tsol tsos tssf tsst tsts ttbb ttff ttss tttt