bbbb bbbs bblb bbls blls blss blub blur blus bly- blys brls brrr brrs brsb brsr brus bry- bubb bubs bubu bulb bull buls bulu bur- burb burl burr burs buru bury buss busu busy buus buyl buys buyu bysb bysl byss bysy byul lblr lbrs llbs llll llyr lrrr lrry ls-r lsbu lssr lubs luby lull lulu lurs lury luss luys lyly lys- lysl lyss rbbb rbbr rbbs rbsl rbss rlls rlys rrrr rssl rubb rubs rubu ruby rull ruly rurs ruru russ rusu rusy ruyl ruys rysy sbbs sbus slrs slsu slub slur slys srby srub ssbr ssby ssrl ssrs sssb ssss sub- subb subl subs sul- sull sulu sur- surr surs suru sury sus- suss susu susy suus suyr suyu syl- syll syls syrs syry syss ubls ubly ullr ully ulul ulus ulys urbs urls urry urss ursu ursy urur urus usbl usbr usbs uslu ussb ussr usss ussu ussy usul usus uulu uuuu ybbs ybry ylls yrly ysby yssu ysyb yubu yuls yulu yury yuyu yyyy