bbbb bbbs bibb bibi bibo bibs biis biko bio- bioi bios birb biri birk biro birr birs bis- bisk biso biss bivi bobb bobi bobo bobs boi- boii bois boki boko boks boob book boor boos bor- bori bork boro borr bors bosi bosk boso boss bovi bovo brik brio bris brkb brob brok broo bror bros brrr brrs brsb brsr brvi bsos ibis ibos ibri ibro ibss iiii iiio iiis iioi iioo iios iirs iisi iisr ikki ikko ikoo ikri iobi ioii ioio ioko iooi iooo ioos iori iors ioso iri- irio iris irki irks irob irov irri irrs irvs isis isko iso- isok isor isos isri issi isso issr isss ivbv ivor ivrs k-os kbbb kbbi kbbk kbbo kbbr kbbs kbib kbik kbio kbis kbkb kbkk kbko kbkr kbkv kbob kboi kbok kboo kbos kbov kbrb kbri kbrk kbro kbrv kbsb kbsi kbsk kbso kbsr kbss kbsv kbvb kbvo kbvr kibb kibi kibo kibr kibs kiii kiik kiis kiki kikk kiko kikr kioi kiok kioo kirb kiri kirk kiro kirr kirs kirv kisi kisk kiso kisr kiss kisv kivi kkbb kkbi kkbo kkbr kkbs kkik kkkk kkob kkoo kkor kkov kkrb kkrk kkro kkrr kkrs kkrv kksi kksr kkss kkvr kkvv kobb kobi kobk kobo kobr kobs koii koir koiv kokb koki kokk koko kokr koks koob kooi kook kooo koor koos koov korb kori kork koro korr kors korv kos- kosb kosi koso kosr koss kovi kovk kovo kovr krbb krbi krbk krbr krib krik krio kris kriv krki krkk krko krkr krks krkv krob kroi krok kroo kror kros krov krrb krri krrk krro krrr krrs krsk krsr krss krsv krvb krvi krvk krvo krvr krvs krvv ksbi ksbr ksbs ksbv ksib ksii ksik ksir ksis ksiv kskb kskk ksko kskr ksks ksob ksoi ksok ksoo ksor ksos ksrb ksro ksrr ksrs ksrv kssi ksso kssr ksss ksvi ksvr kvbr kvik kvir kvis kviv kvob kvoi kvok kvoo kvor kvov kvri kvro kvrr kvrv kvsi kvso kvsr kvss kvsv kvvr kvvs kvvv obbo obis obkb oboi obok obor obos obri obro obsr obss obvi obvs oiii oiko oiks oios okir okko okok okor okro oksi okso oobi oooo ooos oosi orbb orbi orbo orbs ori- orio oris orko oro- orok oror oros orri orro orrs orsi orsk orso orvr orvs osii osik osis oski osoi osoo osor osos osov osro ossb ossi osso ovi- ovis ovo- ovoo rbbb rbbr rbbs rbis rbss rib- ribo ribs riis riki rikk rios riri rirs risi risk riso riss rivo rivs rkos rkss rksv rob- robb robi robo robs roik roio roir rois roki rokk roko rokr roks roob rooi rook roor roos rori rork roro rosi roso ross rovi rovo rovs rrrr rsbi rsis rsos rvik s-ib s-ii s-iv s-os sbbs sbor sbrk sbsi sibi sibo sibs siik siki siko sikr siks sior sios siri sirk siro sirr sirs sisi sisk siss sivi skik skio skir skis skiv skor skov skss sobo sobr sobs soik soir sois soki sokk soko sook soor soos sorb sori soro sorr sors sosi soso soss sosv sovo sovs srib sris sros ssbr ssis ssri ssrs sssb sssi ssss svir svor vibs viii viik viki viko vios virb viri virk viro virr visi visk viso viss vivi vivo vkor voio voir vois voks voor vor- vori voro vors vosi voso voss vovk vrio vris vrsi vvob vvsb vvvv