-ous bbbb bbbs bblb bbls bffl bffs bfts bftt blbt blls blob bloo blot blou blss blst blts blub bluf blus blut bobb bobo bobs bobu boff bofs bofu boll bolo bols bolt bolu boob boof bool boos boot boso boss bost bosu botb boto bots bott bouf boul bous bout bsff bsfs bsos bsts btob btss bttb btus bubb bubo bubs bubu buff bufo bulb bull buls bult bulu buol buss bust busu but- buto buts butt buus fbus ffff ffss fftf flob floo flos flot flou flts flub fluf fluo flus fobs fobt fofo foll folo fols folt foof fool foos foot fosb foso foss fost foto fots fott foul fous fout fsfo fssf ft-l ftlb ftos ftub fubb fubs fubu fuff fufu full fuls fulu fuso fuss fust fusu futo futs futu 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 loul lous lout louu lsbu lsof lsso lsts ltbf ltbl lubs luff luft lufu lull lulu luso luss lust luts obbo obls oblu obol obos obot obss obst obts obus off- offo offs offu ofst ofus olbo olfs ollo olof olos olot olst oltu ooff oofs oolo oooo ooos oost ootb oots oous oslo osoo osos ossb osso ossu osts osul otbs oto- otof otoo otos otso otsu otto otts ottu otus oubs ouff ouls oulu oust out- outb outo outs ouu- s-os sbbs sbot sbst sbus sfls sfos sfss sfsu sfts slft slob sloo slos slot slst slsu slts slub slut sobo sobs sobt sobu sofo soft solf soll solo sols solt soof sool soos soot soso soss sost sotl soto sots sotu souf soul sous sout ssfl sslt ssot sssb sssf ssss sstb sstl ssts stbs stfu stlo stlt stob stof stol stoo stos stot stou stsf stss stub stuf stul stus stut sub- subb subl subo subs suf- suff sufs sufu sul- sulf sull sulo sult sulu suos sus- suso suss sust susu suto sutu suus tbbs tbst tfot tfss tlos tobo tobs tobt tobu toff tofo toft tofu tol- toll tolo tolt tolu toof tool toos toot tosb toso toss tost tosu toto tots tott toul tous tout tsfl tsob tsol tsos tsou tssf tsst tsts ttbb ttff ttss tttt ttul tubb tubo tubs tubu tuff tufo tuft tufu tull tulo tulu tuos tuss tust tutl tuto tuts tutt tutu tuuo ubbo ublo ubls ubos ubtf ufos ulft ullo ulo- ulos ulto ults ultt ulul ulus uofl uofo usbl usbs usfl usfs uslu usos ussb ussf usss usst ussu ustb usto usts usul usus utfo utsl utto uttu uulu uutf uuuu