a-a a-b a-i aaa aab aai aam aar aas ab- aba abb abi abm abr abs ai- aia aib aii aim air ais ama amb ami amm amr ams ar- ara arb ari arm arr ars as- asa asb asi asm asr ass baa bab bai bam bar bas bba bbb bbi bbm bbr bbs bi- bia bib bii bim bir bis bma bmb bmi bmm bmr bms bra brb bri brm brr brs bsa bsb bsi bsm bsr bss ia- iaa iab iai iam iar ias iba ibb ibi ibm ibr ibs iia iib iii iim iir iis im- ima imb imi imm ims ir- ira irb iri irm irr irs is- isa isb isi ism isr iss m-r maa mab mai mam mar mas mba mbb mbi mbm mbr mbs mi- mia mib mii mim mir mis mma mmb mmi mmm mmr mms mra mrb mri mrm mrr mrs msa msb msi msm msr mss ra- raa rab rai ram rar ras rba rbb rbi rbm rbr rbs ria rib rii rim rir ris rma rmb rmi rmm rmr rms rra rrb rri rrm rrr rrs rsa rsb rsi rsm rsr rss saa sab sai sam sar sas sba sbb sbi sbm sbr sbs sia sib sii sim sir sis sma smb smi smm smr sms sr- sra srb sri srm srr srs ss- ssa ssb ssi ssm ssr sss