a-ak a-be aaaa aaab aaae aaav aaba aabb aaea aaev aaka aake aava abaa abab abae abak abb- abba abbb abbe abee abva aeka aeva akaa akae akee akka avab avea avva baaa baak baba babb babe baek bak- baka bake bava bave bbbb bbeb beak beav beba bebb bebe beeb beek beka beke eaba eave ebba eeea eeee eeka eeke eeva eka- ekab ekeb ekek ekka evae evea evvk kaaa kaab kaak kaba kabb kabe kaka kake kakk kava kavb kave kavv kbaa kbab kbae kbak kbba kbbb kbbe kbbk kbeb kbee kbek kbev kbkb kbkk kbkv kbva kbvb kea- keak keba kebb kebe keek keka kekb keke keva keve kkaa kkba kkbb kkbe kkea kkkk kkvv kvab kvak kvea kvvv vaka vake vava veak veba veka veke veve vvvv