a-a a-b a-i aaa aab aai aar aas aay ab- aba abb abi abr abs aby ai- aia aib aii air ais aiy ar- ara arb ari arr ars ary as- asa asb asi asr ass asy ay- aya ayi ayr ays baa bab bai bar bas bay bba bbb bbi bbr bbs bby bi- bia bib bii bir bis biy bra brb bri brr brs bry bsa bsb bsi bsr bss bsy by- bya byi byr bys ia- iaa iab iai iar ias iba ibb ibi ibr ibs iby iia iib iii iir iis ir- ira irb iri irr irs iry is- isa isb isi isr iss isy iya iyr iys iyy ra- raa rab rai rar ras ray rba rbb rbi rbr rbs ria rib rii rir ris riy rra rrb rri rrr rrs rsa rsb rsi rsr rss ry- rya ryr rys ryy saa sab sai sar sas say sba sbb sbi sbr sbs sby sia sib sii sir sis sr- sra srb sri srr srs sry ss- ssa ssb ssi ssr sss sy- sya syb syi syr sys yaa yab yai yar yas yay ybi ybr ybs yby yii yir yis yra yrs ysa ysb ysi ysr yss ysy yyb yys yyy