a-a a-b a-i a-t aaa aab aai aao aar aat aay ab- aba abb abi abo abr abt aby ai- aia aib aii aio air ait aiy aoa aob aoi aoo aor aot ar- ara arb ari aro arr art ary at- ata atb ati ato atr att ay- aya ayi ayo ayr ayt baa bab bai bao bar bat bay bba bbb bbi bbo bbr bbt bby bi- bia bib bii bio bir bit biy boa bob boi boo bor bot boy bra brb bri bro brr brt bry bta btb bti bto btr btt bty by- bya byi byo byr byt ia- iaa iab iai iao iar iat iba ibb ibi ibo ibr ibt iby iia iib iii iio iir iit io- ioa iob ioi ioo ior iot ir- ira irb iri iro irr irt iry ita itb iti ito itt ity iya iyo iyr iyt iyy o-i oaa oab oai oao oar oat ob- oba obb obi obo obr obt oby oia oib oii oio oir oit oo- ooa oob ooi ooo oor oot or- ora orb ori oro orr ort ory ot- ota otb oti oto otr ott oya oyi oyo ra- raa rab rai rao rar rat ray rba rbb rbi rbo rbr rbt ria rib rii rio rir rit riy roa rob roi roo ror rot roy rra rrb rri rrr rrt rta rtb rti rto rtr rtt rty ry- rya ryo ryr ryy taa tab tai tao tar tat tay tba tbb tbi tbo tbr tbt tia tib tii tio tir tit tiy to- toa tob toi too tor tot toy tra trb tri tro trr trt try tta ttb tti tto ttr ttt tty tya tyo tyr tyt yaa yab yai yao yar yat yay ybi ybr yby yii yio yir yit yob yoi yoo yor yot yoy yra yro yrt yta yto ytr ytt yyb yyt yyy