a-ak a-ok aaaa aaab aaas aaav aaba aabb aaka aaoo aasa aass aava abaa abab abak abas abb- abba abbb abbo abbs aboa abob abok aboo abos abov abs- absa abss abva akaa akao akas akka akko akok akos aksa aoba aoks aoss asaa asab asak asao asas asba asbo aska asko asks asob asok asos assa assk asso asss asva asvs avab avao avas avos avva avvo baaa baak baas baba babb babo babs bak- baka bako baks baos basa bask baso bass bava bbas bbbb bbbs boab boak boas boba bobb bobo bobs boka boko boks boob book boos bosa bosk boso boss bova bovo bsaa bsas bsos k-os kaaa kaab kaak kaas kaba kabb kabo kaka kakk kako kaks kaoa kaok kaos kas- kasa kasb kask kaso kass kava kavb kavo kavs kavv kbaa kbab kbak kbas kbba kbbb kbbk kbbo kbbs kbkb kbkk kbko kbkv kboa kbob kbok kboo kbos kbov kbsa kbsb kbsk kbso kbss kbsv kbva kbvb kbvo kkaa kkba kkbb kkbo kkbs kkkk kkoa kkob kkoo kkov kksa kkss kkvv koab koak koas koba kobb kobk kobo kobs koka kokb kokk koko koks koob kook kooo koos koov kos- kosa kosb koso koss kova kovk kovo ksab ksak ksas ksav ksba ksbs ksbv kska kskb kskk ksko ksks ksob ksok ksoo ksos kssa ksso ksss ksva kvab kvak kvas kvoa kvob kvok kvoo kvov kvsa kvso kvss kvsv kvvs kvvv oaks oass oavs obak obas obba obbo obkb obok obos obss obvs okak okas okka okko okok oksa okso ooaa ooak ooba oooo ooos oosa osak osas osba osoo osos osov ossa ossb osso ovo- ovoo s-os saab saak saas saba sabb sabo sabs saka sakb sakk sako saks saos sasa sask saso sass sava savo savs sbaa sbas sbbs sbsa skab skov skss soak soas soba sobo sobs soka sokk soko sook soos sosa soso soss sosv sova sovo sovs ssaa ssab ssao ssas sssa sssb ssss vaas vabs vaka vas- vasa vaso vass vava vavs voka voks vosa voso voss vovk vvob vvsb vvvv