a-a a-b a-t aaa aab aad aao aar aat aay ab- aba abb abd abo abr abt aby ad- ada adb add ado adr adt ady aoa aob aod aoo aor aot ar- ara arb ard aro arr art ary at- ata atb atd ato atr att ay- aya ayd ayo ayr ayt baa bab bad bao bar bat bay bba bbb bbd bbo bbr bbt bby bda bdb bdd bdo bdr bdt bdy boa bob bod boo bor bot boy bra brb brd bro brr brt bry bta btb btd bto btr btt bty by- bya byd byo byr byt daa dab dad dao dar dat day dba dbb dbd dbo dbr dbt dby dda ddb ddd ddo ddr ddt ddy doa dob dod doo dor dot doy dra drb drd dro drr drt dry dta dtb dtd dto dtr dtt dty dy- dya dyb dyd dyo dyr dyy oaa oab oad oao oar oat ob- oba obb obd obo obr obt oby oda odb odd odo odr odt oo- ooa oob ood ooo oor oot or- ora orb ord oro orr ort ory ot- ota otb otd oto otr ott oya oyd oyo ra- raa rab rad rao rar rat ray rba rbb rbd rbo rbr rbt rda rdb rdd rdo rdr rdt rdy roa rob rod roo ror rot roy rra rrb rrd rrr rrt rta rtb rtd rto rtr rtt rty ry- rya ryd ryo ryr ryy taa tab tad tao tar tat tay tba tbb tbd tbo tbr tbt tda tdb tdd tdo tdr tdt tdy to- toa tob tod too tor tot toy tra trb trd tro trr trt try tta ttb ttd tto ttr ttt tty tya tyd tyo tyr tyt yaa yab yad yao yar yat yay ybr yby yda ydo ydt ydy yob yod yoo yor yot yoy yra yro yrt yta ytd yto ytr ytt yyb yyt yyy