ffff ffrr ffss fmsr fmss frsm frum frys fssf fuff fufu fums fumy fur- furm furr furs fury fuss fusu fuyu fyrs fyry mfrs mmff mmmm mmms mmrf mmsu mmus mmyy msff msfs msmm msms msmu mssf mssm mssr msus muff mufu mumm mums mumu mumy murr murs muru mury muss musu muys mymy myrr myry mys- myss myus myys rrrr rrum rsum ruff rumm rums rumy rurs ruru russ rusu rusy ruys ryff rysy ryyf sfmm sfss sfsu smrf smry smss smur smus ssrm ssrs sssf sssm ssss suf- suff sufr sufs sufu sum- sums sumu sumy sur- surf surr surs suru sury sus- suss susu susy suum suus suyr suyu syff syfy sym- syms syrs syry syss ufms umff umms umsu umus urff urry urss ursu ursy urum urur urus usfs usmm usms ussf ussr usss ussu ussy usus uuuu ymur yssu yuff yufu yury yuyu yyff yyyy