a-ak a-ok aaaa aaab aaav aaba aabb aabt aaka aaoo aata aatk aatt aava abaa abab abak abat abb- abba abbb abbo abbt aboa abob abok aboo abot abov abta abva akaa akao akka akko akok akot aktv aoba at-t ataa atab atak atat atka atkt atkv atob atok atot atta atto avab avao avat avkt avot avva avvo baaa baak baat baba babb babo bak- baka bako bakt bata bato batt bava bbbb boab boak boat boba bobb bobo boka boko boob book boot bota botb boto bott bova bovo btaa btob bttb kaaa kaab kaak kaat kaba kabb kabo kaka kakk kako kakt kaoa kaok kat- kata katb katk kato katt katv kava kavb kavo kavv kbaa kbab kbak kbat kbba kbbb kbbk kbbo kbbt kbkb kbkk kbko kbkv kboa kbob kbok kboo kbot kbov kbta kbtb kbtk kbto kbtt kbtv kbva kbvb kbvo kkaa kkat kkba kkbb kkbo kkbt kkkk kkoa kkob kkoo kkot kkov kktk kktv kkvt kkvv koab koak koba kobb kobk kobo koka kokb kokk koko koob kook kooo koot koov kota kotb kotk koto kott kotv kova kovk kovo ktaa ktak ktao ktat ktav ktba ktbb ktbt ktkb ktkk ktko ktkt ktob ktok ktoo ktot kttk ktto kttt kttv ktva ktvb ktvk ktvo ktvt kvab kvak kvat kvbt kvoa kvob kvok kvoo kvot kvov kvta kvtk kvto kvtt kvtv kvvv obak obba obbo obkb obok obot okak okka okko okok okot okta okto ooaa ooak ooba oooo ootb otak oto- otok otoo otov otta otto ovo- ovoo ovot taa- taat taba tabb tabo taka takk tako takt taoa tata tatb tato tatt tatv tava tavo tbta toab toat toba tobo tobt toka toko tooa took toot tota toto tott tova tovo ttab ttbb tttt tvtv vaat vaka vata vato vatt vava voat voka voot vota voto vovk vvob vvvv