bbuss blubs bluff blufr blurb blurr blurs bplus brrrr bruff brull bruss buffs bulb- bulbs bull- bulls bulul bulus burbs burls burps burrs burru burus bussu busur busuu flubs fluff flurb flurr fluss fu-fu fubbs fubus fuffs fullf fulls fulup furls furps furrs furus fusus llrrs lubur luffs lulls lulul lulus lupsu lupul lupus lurup lusus pluff plupp pruss puffs pull- pulls pullu pulps purls purrs purul purus puurs rrsps rsssf rubup rubus ruffs rufus s-bus slubs sluff slurb slurf slurp slurs sluss spurl spurr spurs spuul srprb ssbul sssrb sssss subbu subss suffr suffs suflu sulf- sulls sulur sulus supls suppl supps supur surbl surfs surpu surul surur surus susus ullur ulpur ululu uluru ursus urubu usurp uuuuu