-al -ol a-a a-b aaa aab aal aao aar aas ab- aba abb abl abo abr abs al- ala alb all alo alr als aoa aob aol aoo aor aos ar- ara arb arl aro arr ars as- asa asb asl aso asr ass baa bab bal bao bar bas bba bbb bbl bbo bbr bbs bla blb bll blo blr bls boa bob bol boo bor bos bra brb brl bro brr brs bsa bsb bsl bso bsr bss la- laa lab lal lao lar las lba lbb lbl lbo lbr lbs lla llb lll llo llr lls loa lob lol loo lor los lra lrb lro lrr lrs lsa lsb lsl lso lsr lss oaa oab oal oao oar oas ob- oba obb obl obo obr obs ola olb oll olo ols oo- ooa oob ool ooo oor oos or- ora orb orl oro orr ors os- osa osb osl oso osr oss ra- raa rab ral rao rar ras rba rbb rbl rbo rbr rbs rla rll rlo rlr rls roa rob rol roo ror ros rra rrb rrl rrr rrs rsa rsb rsl rso rsr rss saa sab sal sao sar sas sba sbb sbl sbo sbr sbs sla slb sll slo slr sls soa sob sol soo sor sos sr- sra srb srl sro srr srs ss- ssa ssb ssl sso ssr sss