bbbee be-er bebel beber beebe beele beffe befur belee belef bellb belle belue belur berbe berel berle berre berru beuer beule beure bleer blere bleue bluer bluff blufr blurb blure blurr brebu breef breel breer brell brere breu- brrrr bruer bruff brule brull bubbe buber buble buell buffe bufle bulb- bull- bulle bulul burel burle burru ebber ebble ebell eberl eblul ebull ebure eeeee eeler efere effer efuru elele ellel eller ellul elulu eluru erbbe erber erere euell euler eurel eurre febel feble febre feele feere felle ferel ferle ferr- ferre feuer feule fleer flere fleur fluff flurb flure flurr freel freer frere freur fu-fu fulbe fulle fullf furel lebel leber leell leere lefeu leffe leful leleu lelle lerer lubbe luber luble lubur lufre lulle lulul lurer lurue rebbe rebel reber reefe reere refel refer reffe relee relue rere- reree reuel reuer reule rubee rubel ruber ruble ruele ruell ruere ruffe ruler ruule ubble uber- uelfe ufere ullur ululu uluru urelu urubu uuuuu