k-os kkkk kkoo kkor kkot kkov kkrk kkro kkrr kkrs kkrt kkrv kksr kkss kkst kktk kkts kktv kkvr kkvt kkvv kokk koko kokr koks kook kooo koor koos koot koov kork koro korr kors kort korv kos- koso kosr koss kost kotk koto kotr kots kott kotv kovk kovo kovr krkk krko krkr krks krkv krok kroo kror kros krov krrk krro krrr krrs krrt krsk krsr krss krst krsv krtk krto krtr krts krtv krvk krvo krvr krvs krvv kskk ksko kskr ksks ksok ksoo ksor ksos ksro ksrr ksrs ksrt ksrv ksso kssr ksss ksst kstk ksto kstr ksts kstt kstv ksvr ktkk ktko ktkr ktks ktkt ktok ktoo ktor ktot ktrk ktro ktrr ktrs ktrt ktrv ktso ktsr ktst kttk ktto kttr ktts kttt kttv ktvk ktvo ktvr ktvt kvok kvoo kvor kvot kvov kvro kvrr kvrv kvso kvsr kvss kvst kvsv kvtk kvto kvtr kvtt kvtv kvvr kvvs kvvv okko okok okor okot okro okso okto oooo ooos oort oost oots orko oro- orok oror oros orot orro orrs orsk orso orto orts orvr orvs osoo osor osos osov osro osso ostr osts oto- otok otoo otor otos otov otro otrs otso otto otts ovo- ovoo ovot rkos rkss rksv rkts rokk roko rokr roks rook roor roos root rork roro rort roso ross rost rotk roto rotr rots rott rovo rovs rrrr rsos rsts rtss rtts s-os s-vt skor skot skov skrt skss sokk soko sook soor soos soot soro sorr sors sort soso soss sost sosv sotk soto sots sovo sovs sros srtr srtv ssot ssrs ssss ssts st-v stks stok stoo stor stos stot strk stro strs stss sttr stvs svor svtr tkos tkts toko took toor toos toot tork toro torr tors tort torv tosk toso toss tost toto totr tots tott tovo troo tros trot trst trtr trvs tsks tsos tssr tsst tsts ttss tttt tvos tvro tvrr tvss tvtv vkor voks voor voot vor- voro vors vort voso voss voto vovk vrot vrto vsto vtrs vvvv