-al -ol a-a a-b aaa aab aaf aak aal aao ab- aba abb abf abk abl abo af- afa afb aff afk afl afo aka akb akk akl ako al- ala alb alf alk all alo aoa aob aof aok aol aoo baa bab baf bak bal bao bba bbb bbf bbk bbl bbo bfa bfb bff bfl bfo bka bkb bkf bkk bkl bko bla blb blf blk bll blo boa bob bof bok bol boo faa fab faf fak fal fao fba fbb fbf fbk fbl fbo ffa fff ffk ffl ffo fka fkb fkf fkk fkl fla flb flf fll flo foa fob fof fok fol foo ka- kaa kab kaf kak kal kao kba kbb kbf kbk kbl kbo kfa kff kfo kkb kkk kkl kl- kla klb klf klo koa kob kof kok kol koo la- laa lab laf lak lal lao lba lbb lbf lbk lbl lbo lfa lfb lff lfk lfl lfo lka lkb lkl lla llb llf llk lll llo loa lob lof lok lol loo oaa oab oaf oak oal oao ob- oba obb obf obk obl obo of- ofa ofb off ofl ofo oka okb okk okl oko ola olb olf olk oll olo oo- ooa oob oof ook ool ooo