-ous bbbb bbbs bobb bobo bobs bobu boob boor boos boot booz bor- boro borr bors bort boru borz boso boss bost bosu botb boto bots bott bour bous bout bozo brob broo bror bros brot brou broz brrr brrs brsb brsr brst brus brut bruz bsos bsts btob btor btrt btss bttb btus bubb bubo bubs bubu bur- burb buro burr burs burt buru burz buss bust busu but- buto buts butt butz buus buuz buzz bzou bzzt bzzz obbo obor obos obot obro obsr obss obst obts obus oooo ooos oort oost ootb oots oous orbb orbo orbs orbu oro- oror oros orot oroz orro orrs orso orsu orto orts orub orus orzo orzu osoo osor osos osro ossb osso ossu ostr osts otbs oto- otoo otor otos otro otrs otso otsu otto otts ottu otur otus oubs our- ouro ours ourt oust out- outb outo outs ouu- ouzo rbbb rbbr rbbs rbss rbst rob- robb robo robs robt robu roob roor roos root rooz roro rort roru roso ross rost roto rotr rots rott roub rous rout rouz rozz rrrr rsos rsts rstu rtss rtts rubb rubs rubu ruro rurs ruru ruso russ rust rusu ruto ruts rutt rutu s-os sbbs sbor sbot sbst sbus sobo sobr sobs sobt sobu soor soos soot sorb soro sorr sors sort soru soso soss sost soto sots sotu sour sous sout soz- sros srtr srub srzu ssbr ssot ssrs sssb ssss sstb ssts stbs stob stoo stor stos stot stou stro strs stru stss sttr stub stur stus stut sub- subb subo subs subz suor suos sur- suro surr surs surt suru sus- suso suss sust susu susz suto sutu suus suzo suzu suzz szob szot szss szur tbbs tbrb tbst tobo tobs tobt tobu toor toos toot toro torr tors tort toru tosb toso toss tost tosu toto totr tots tott tour tous tout tozo troo tros trot trou trst trtr trub trus trut truu tsob tsos tsou tssr tsst tsts ttbb ttss tttt tubb tubo tubr tubs tubu tuor tuos turb turo turr turs turt turu tuss tust tuto tuts tutt tutu tuuo tuzu tuzz tzur tzus tzut tzzt ubbo ubos uor- urbs uro- uroo urso urss ursu urts urur urus urut uruz usbr usbs usos ussb ussr usss usst ussu ustb usto usts usus utor utto uttu uuuu uzos z-ro zbus zobo zoo- zoos zoot zorb zoro zors zort zoso zoss zots zott zotz zozo zozu zsss ztst zubo zubr zubu zuoz zurb zurr zuru zust zuzu zzzs zzzz