bbbee be-er be-ro beber beebe beffe befoe befor beofe beoff berbe berob beroe beror berre bo-bo bobr bobre boero boffo booer boore borbo boree borer boro- boroo borre borro breef breer breo- brere brobo broer brrrr ebber eeeee efere effer efore eofor eorre erbbe erber erere eroor erore error febre feeor feere fefor feoff ferr- ferre ferro foore fore- foreo forro freer frere frobe frore o-fer o-r-b oboro obreb offer offof offre oo-er ooooo oreo- orere orero orfeo orfoe orfor orobe orobo oroer rebbe reber reefe reere refer reffe reffo rere- reree rerob ro-ro robbe robbo rober robo- robor roero roffe rofor rooer roofe roore rorer