bbbb bbdd bbdo bd-r bdii bibb bibi bibo bidi bido bidr bio- bioi biot birb bird biri biro birr birt bitd bito bitt bitz bizz bobb bobi bobo bodb bodi bodo boi- boid boii boit boob bood boor boot booz bor- bord bori boro borr bort borz botb botd boti boto bott bozi bozo brdo brdt brid brio brit briz brob brod broo bror brot broz brrr btdt btob btor btrt bttb bzzt bzzz d-bo dbit dbtt dddd ddot dibb dibo didi dido diii dior diot dird dirr dirt diti dito ditt ditz dizi dizz dobb dobi dod- dodd dodi dodo doid doit doob dood door doot dord dori doro dorr dort dotd doti doto dott dozi dozo drib drit drob drod drot droz dtor dtot dzbb dzor dzrr ibdo ibid ibot ibrd ibri ibro ibtb iddo idid idio idir idro iiii iiio iiit iioi iioo iitr iitt iobi iod- iodd iodo ioii ioio ioit iooi iooo iori ioto irdo iri- irid irio irob irod irri irti itdo itoi itoo itor itri itto izod izzo obbo obdt obid obit oboi obor obot obri obro obtd odbo oddd oddi odio odir odoo odor odot odzi oido oiii oirt oiti oitz oobi oodi ooid oooo oord oort ootb oozi orbb orbi orbo ordo ori- orid orio orit oro- oror orot oroz orri orro orto orzo otbd otit oto- otoo otor otro otti otto otzi ozd rbbb rbbr rdio rib- ribo ridd ridi rido riot rioz riri riti rito ritt ritz rizi rizz rob- robb robi robo robt rodd rodi rodo roid roio roir roit roiz roob rood rooi roor root rooz rori roro rort roti roto rotr rott rozi rozz rrrr rtdt tbit tbrb tddb tdor tdri tibi tidd tiit tirb tird tiri tiro tirr titi tito titt titz tizi tizz tobi tobo tobt todd todi todo todt toid toit tood toor toot tord tori toro torr tort totd toti toto totr tott tozo tri- trib trio trit triz trod troi troo trot trtr ttbb tttt tzzt z-ro zibo zidi ziri ziro ziti zito zizi zizz zobo zodd zodi zoid zoio zoo- zoot zorb zord zori zoro zort zoti zott zotz zozo zzzz