bbbb bbdd bbdo bd-r bdii bibb bibi bibo bidi bido bidr bio- bioi birb bird biri biro birr bobb bobi bobo bodb bodi bodo boi- boid boii boob bood boor bor- bord bori boro borr brdo brid brio brob brod broo bror brrr d-bo dddd dibb dibo didi dido diii dior dird dirr dobb dobi dod- dodd dodi dodo doid doob dood door dord dori doro dorr drib drob drod ibdo ibid ibrd ibri ibro iddo idid idio idir idro iiii iiio iioi iioo iobi iod- iodd iodo ioii ioio iooi iooo iori irdo iri- irid irio irob irod irri obbo obid oboi obor obri obro odbo oddd oddi odio odir odoo odor oido oiii oobi oodi ooid oooo oord orbb orbi orbo ordo ori- orid orio oro- oror orri orro rbbb rbbr rdio rib- ribo ridd ridi rido riri rob- robb robi robo rodd rodi rodo roid roio roir roob rood rooi roor rori roro rrrr