-al -ol a-a a-b aaa aab aak aal aao aas ab- aba abb abk abl abo abs aka akb akk akl ako aks al- ala alb alk all alo als aoa aob aok aol aoo aos as- asa asb ask asl aso ass baa bab bak bal bao bas bba bbb bbk bbl bbo bbs bka bkb bkk bkl bko bks bla blb blk bll blo bls boa bob bok bol boo bos bsa bsb bsk bsl bso bss ka- kaa kab kak kal kao kas kba kbb kbk kbl kbo kbs kkb kkk kkl kks kl- kla klb klo kls koa kob kok kol koo kos ksa ksb ksk ksl kso kss la- laa lab lak lal lao las lba lbb lbk lbl lbo lbs lka lkb lkl lks lla llb llk lll llo lls loa lob lok lol loo los lsa lsb lsk lsl lso lss oaa oab oak oal oao oas ob- oba obb obk obl obo obs oka okb okk okl oko oks ola olb olk oll olo ols oo- ooa oob ook ool ooo oos os- osa osb osk osl oso oss saa sab sak sal sao sas sba sbb sbk sbl sbo sbs sk- ska skb skk skl sko sks sla slb slk sll slo sls soa sob sok sol soo sos ss- ssa ssb ssk ssl sso sss