bbbb bbbs bbdd bd-r bdii bdsd bibb bibi bibs bidi bidr bids bidu biis birb bird biri birr birs biru bis- bisd biss bisu brds brid bris brrr brrs brsb brsr brud brus bsbd bsrd bssd bubb bubi bubs bubu budb budd budi buds budu buid buir buis buiu bur- burb burd buri burr burs buru busi buss busu buus dbrs dbss dbus dddd ddss ddub dibb dibs didi dids didu diii diis dird dirr dirs dis- disd disi diss dius drib drrs drub drui drus druu dsdr dsri dsrr dssi dub- dubb dubs dubu dudd duds dudu duid duir duis duri duru dusi duur ibid ibis ibrd ibri ibss ibus idid idir idis idss idub idus iiii iiis iirs iisd iisi iisr iisu irds iri- irid iris irri irrs irus isbd isdb isds isis isri issi issr isss issu isus iuds iuiu iusd iuss rbbb rbbr rbbs rbds rbis rbsd rbss rib- ribs ribu ridd ridi rids riis riri rirs risd risi riss risu rius rrrr rsbi rsdd rsds rsid rsis rubb rubi rubs rubu rudd rudi ruds ruid ruis rurd ruri rurs ruru rusi russ rusu ruud s-ib s-ii sbbs sbds sbsd sbsi sbus sdds sdib sdrs sdss sdsu sibi sibs sibu sidd sidi sidr sids siri sirr sirs siru sisd sisi siss sisu siui sius srib sris srsd srub ssbr ssdd ssid ssis ssri ssrs sssb sssi ssss sub- subb subd subi subs sudd sudi suds suid suir suis sur- surd suri surr surs suru sus- susd susi suss susu suus ubbi ubid ubii ubir ubis ubud uddi udds udid udir udsd uirr uisd urbi urbs urds urdu urib uris uriu urri ursi urss ursu urur urus usbr usbs usds usis ussb ussr usss ussu usui usus uuri uusi uuuu