-al -ol a-a a-b a-i aaa aab aai aal aao aar aas ab- aba abb abi abl abo abr abs ai- aia aib aii ail aio air ais al- ala alb ali all alo alr als aoa aob aoi aol aoo aor aos ar- ara arb ari arl aro arr ars as- asa asb asi asl aso asr ass baa bab bai bal bao bar bas bba bbb bbi bbl bbo bbr bbs bi- bia bib bii bil bio bir bis bla blb bli bll blo blr bls boa bob boi bol boo bor bos bra brb bri brl bro brr brs bsa bsb bsi bsl bso bsr bss ia- iaa iab iai ial iao iar ias iba ibb ibi ibl ibo ibr ibs iia iib iii iil iio iir iis il- ila ilb ili ill ilo ilr ils io- ioa iob ioi iol ioo ior ios ir- ira irb iri irl iro irr irs is- isa isb isi isl iso isr iss la- laa lab lai lal lao lar las lba lbb lbi lbl lbo lbr lbs lia lib lii lil lio lir lis lla llb lli lll llo llr lls loa lob loi lol loo lor los lra lrb lri lro lrr lrs lsa lsb lsi lsl lso lsr lss o-i oaa oab oai oal oao oar oas ob- oba obb obi obl obo obr obs oia oib oii oil oio oir ois ola olb oli oll olo ols oo- ooa oob ooi ool ooo oor oos or- ora orb ori orl oro orr ors os- osa osb osi osl oso osr oss ra- raa rab rai ral rao rar ras rba rbb rbi rbl rbo rbr rbs ria rib rii ril rio rir ris rla rli rll rlo rlr rls roa rob roi rol roo ror ros rra rrb rri rrl rrr rrs rsa rsb rsi rsl rso rsr rss saa sab sai sal sao sar sas sba sbb sbi sbl sbo sbr sbs sia sib sii sil sio sir sis sla slb sli sll slo slr sls soa sob soi sol soo sor sos sr- sra srb sri srl sro srr srs ss- ssa ssb ssi ssl sso ssr sss