bbbb bbbs bbdd bdsd bnss bsbd bsnd bsns bssd bsts btdt btss bttb btus bubb bubs bubu budb budd buds budu bunb bund bunn buns bunt bunu buss bust busu but- buts butt buus dbss dbtt dbus dddd ddss ddts ddub dntt dnus dnut dssn dsst dstn dsts dtnb dtss dub- dubb dubs dubu dudd duds dudu dunn duns dunt dust duts duut nddb ndnt ndss ndut nndb nnnn nnss nntn nsds nsdt nssb nsss nstd nsts nstu nsub ntds ntnd ntnu ntsb ntss ntsu nubs nudd nunn nuns nunt nuss nust nusu nuts nutt nutu sbbs sbds sbsd sbst sbtn sbus sdds sdss sdsu snns snsd snub snus ssbn ssdd ssns sssb ssss sstb sstd ssts stbd stbs stds stnd stnn stns stss sttd stub stud stun stus stut sub- subb subd subs sudd suds sun- sunb sund sunn suns sunt sunu sus- susd suss sust susu sutu suus tbbs tbst tddb tdss tndd tnts tnut tsbd tsdb tsst tsts tsun ttbb ttss tttt tubb tubs tubu tudu tunb tund tunn tuns tunu tusd tuss tust tuts tutt tutu ubud udds udsd udts udun unbd unds unns uns- unst untb unts unus unut usbs usds usdt usnu ussb usss usst ussu ustb usts usun usus uttu uuuu