a-a a-b aaa aab aad aag aar aau ab- aba abb abd abg abr abu ad- ada adb add adg adr adu ag- aga agb agd agg agr agu ar- ara arb ard arg arr aru au- aua aub aud aug aur b-u baa bab bad bag bar bau bba bbb bbd bbg bbr bbu bda bdb bdd bdg bdr bdu bga bgb bgd bgg bgr bgu bra brb brd brg brr bru bua bub bud bug bur buu daa dab dad dag dar dau dba dbb dbd dbg dbr dbu dda ddb ddd ddg ddr ddu dga dgd dgg dgr dgu dra drb drd drg drr dru dua dub dud dug dur g-d gaa gab gad gag gar gau gba gbd gbg gbr gbu gda gdb gdd gdr gdu gga ggb ggd ggg ggr ggu gra grb grd grg grr gru gu- gua gub gud gug gur guu ra- raa rab rad rag rar rau rba rbb rbd rbg rbr rbu rda rdb rdd rdg rdr rdu rga rgb rgd rgg rgr rra rrb rrd rrg rrr rru rua rub rud rug rur ruu ua- uaa uab uad uag uar uau uba ubb ubg ubr ubu uda udb udd udg udr udu uga ugb ugg ugr ugu ur- ura urb urd urg urr uru uua uug uur uuu