bbbee be-er be-ro beber beebe beeri beibi beier beire beoir berbe berei berie berio berob beroe beror berre berri bibbe bibbo biber bibie bibio bibri biebe biere bieri biore birie bo-bo bobbi bobr bobre bobri boero boibe boier boire boiro booer boore borbo boree borer borio boro- boroo borre borro breer breo- brere bribe brier brobo broer brrrr ebber ebbie ebibe ebrio eeeee eerie eieio eirie eorre erbbe erber erere erier erio- eroor erore error i-beo ibero ibibo ibore ieiri ierei ieroe iiiee iiiii ioooi ioooo iorio irobo irori o-r-b obeie oboro obreb oeiro oo-er ooioo ooooo oorie orebi oreo- oreoi orere orero oribe oribi orobe orobo oroer rebbe reber reere rere- reree rerir rerob ribbi riber ribie ribo- ririe ro-ro robbe robbi robbo rober robie robo- robor roero rooer roore rorer