a-be a-do aaaa aaab aaad aaae aaaf aaba aabb aabd aada aade aaea aafa aafb aafd aaff aaoe aaoo abaa abab abad abae abaf abb- abba abbb abbe abbo abda abdo abed abee abff aboa abob abod abof aboo adaa adab adad adae adao adba adda addd adde addo adea adeb adee adeo adfa adob adod adoe adoo aeaf aede afaa afad afao afdb afee affa affo afoa afoe afoo aoba baaa baad baaf baba babb babe babo bada badb badd bade bado baed baff bafo bbad bbbb bbdd bbdo bbeb bead beaf beba bebb bebe bebo beda bede bedo beeb beed beef befa befe beff befo beo- beod beof boab boad boba bobb bobe bobo boda bodb bode bodo boea boee boef boeo bofa bofd bofe boff boob bood booe boof d-bo daab daad daae daba dabb dabo dada dade dado daeb dafa dafe daff dafo dbfo dddd dead deae deaf deba debe deda dedd dede dedo deeb deed deef defe deff defo dfaf dffa dfoe doab doae doba dobb dobe dod- doda dodd dode dodo doea doff doob dood doof eaaf eaba eada eadb eadd eafb ebba ebbo ebed eboe eboo edad edda edde eddo ede- edea edfa edod eede eeea eeee eefa eefe efab efda efeo effa eode faaa faad faba fabd fabe fabo fada fadd fade fado faeb fafa fafe faff fafo fdoa fead feaf feba febo feda fede feeb feed fefe feff fefo feod feof ffee ffff foad foaf foba foda fode foed fofo food foof o-eo oade oafo obad obba obbo obea obed oboe odbo odda oddd odea oded odeo odoo oedo off- offa offe offo ooaa ooba oobe ooda ooff oooo