a-a a-b a-z aaa aab aag aar aau aaz ab- aba abb abg abr abu abz ag- aga agb agg agr agu agz ar- ara arb arg arr aru arz au- aua aub aug aur auz az- aza azb azg azu azz b-u baa bab bag bar bau baz bba bbb bbg bbr bbu bga bgb bgg bgr bgu bgz bra brb brg brr bru brz bua bub bug bur buu buz bza bzr bzu bzz gaa gab gag gar gau gaz gba gbg gbr gbu gbz gga ggb ggg ggr ggu ggz gra grb grg grr gru gu- gua gub gug gur guu guz gza gzr gzu ra- raa rab rag rar rau raz rba rbb rbg rbr rbu rga rgb rgg rgr rra rrb rrg rrr rru rua rub rug rur ruu ruz rza rzb ua- uaa uab uag uar uau uaz uba ubb ubg ubr ubu uga ugb ugg ugr ugu ur- ura urb urg urr uru urz uua uug uur uuu uza uzb uzu z-g zaa zab zag zar zaz zbb zbr zgb zgg zub zug zur zuz zzr zzz