-ous bbbb bbbs bbpr bffs bfpo bfpp bfsr bobb bobo bobs bobu boff bofs bofu boob boof boop boor boos bopp bops bor- borf boro borr bors boru boso boss bosu bouf boup bour bous bpsu brfu brob broo bror bros brou brrr brrs brsb brsr brup brus bsff bsfs bsos bspp bspr bsup bubb bubo bubs bubu buff bufo bufr bups bur- burb buro burp burr burs buru buss busu buus fbop fbrs fbus ffff ffps ffrr ffss fobs fofo foof foos fopp fops for- forb foro forr fors fosb foso foss foup four fous fprf frob frop fros frou frps frsb frso frub fsfo fspf fssf fssp fubb fubs fubu fuff fufu fuor fur- furo furr furs fuso fuss fusu obbo obor obos obro obsr obss obus off- offo offr offs offu ofor ofus ooff oofs oooo ooos oops oous opo- opor opos oppo opps opsu opus orbb orbo orbs orbu orff orfs orfu oro- orof oror oros orps orro orrs orso orsu orub orup orus osbp osoo osor osos osro ossb osso ossu oubs ouff our- ouro ours ouu- pbrf pbrs pbsp pfff pffr pfps pobo pobs poff poof poop poor poos pop- popo popp pops porb poro porr pors posb poso poss pouf poup pour pous ppos pppo pppp ppps pprf ppru ppsf ppss ppur prbs prfs pro- prob prof proo prop pros prou prps prrs prso prss pruf prus pruu psbr psfs psos psou pspp pspr psps psrp psso pubs pubu puff pups pupu pur- purb puro purp purr purs puru puss rbbb rbbr rbbs rbsp rbss rob- robb robo robs robu roff rofo roob roof roop roor roos ropo rops roro roru roso rosp ross roub rouf roup rous rpob rpof rpos rpps rrrr rrsp rsos rspb rspo rsps rubb rubp rubs rubu ruff rufo rupp ruro rurp rurs ruru ruso russ rusu s-os sbbs sbor sbsp sbus sfor sfos sfro sfss sfsu sobo sobp sobr sobs sobu sofo soof soop soor soos sopo sopp sops sopu sorb soro sorr sors soru soso soss souf soup sour sous spfs spoo spop spor spos sppf spps spro sprs spso spsp spss spur spus sros srps srsp srub ssbr ssfp ssop sspf sspo ssps ssrs sssb sssf ssss sub- subb subo subs suf- suff sufr sufs sufu suor suos sup- supo supp supr sups sur- surf suro surp surr surs suru sus- suso susp suss susu suus u-rp ubbo ubos ufos ufpb uofo uor- upor upos uppp uppu upup urbs urff uro- uroo urpo urso urss ursu urup urur urus usbr usbs usfs usos uspo uspp usps ussb ussf ussr usss ussu usus uuuu