a-ak a-ok aaaa aaab aaba aabb aabt aaka aaoo aata aatk aatt abaa abab abak abat abb- abba abbb abbo abbt aboa abob abok aboo abot abta akaa akao akka akko akok akot aoba at-t ataa atab atak atat atka atkt atob atok atot atta atto baaa baak baat baba babb babo bak- baka bako bakt bata bato batt bbbb boab boak boat boba bobb bobo boka boko boob book boot bota botb boto bott btaa btob bttb kaaa kaab kaak kaat kaba kabb kabo kaka kakk kako kakt kaoa kaok kat- kata katb katk kato katt kbaa kbab kbak kbat kbba kbbb kbbk kbbo kbbt kbkb kbkk kbko kboa kbob kbok kboo kbot kbta kbtb kbtk kbto kbtt kkaa kkat kkba kkbb kkbo kkbt kkkk kkoa kkob kkoo kkot kktk koab koak koba kobb kobk kobo koka kokb kokk koko koob kook kooo koot kota kotb kotk koto kott ktaa ktak ktao ktat ktba ktbb ktbt ktkb ktkk ktko ktkt ktob ktok ktoo ktot kttk ktto kttt obak obba obbo obkb obok obot okak okka okko okok okot okta okto ooaa ooak ooba oooo ootb otak oto- otok otoo otta otto taa- taat taba tabb tabo taka takk tako takt taoa tata tatb tato tatt tbta toab toat toba tobo tobt toka toko tooa took toot tota toto tott ttab ttbb tttt