-al -ol a-a a-b a-t aaa aab aaf aal aan aao aat ab- aba abb abf abl abn abo abt af- afa afb aff afl afn afo aft al- ala alb alf all aln alo alt an- ana anb anf anl ann ano ant aoa aob aof aol aon aoo aot at- ata atb atf atl atn ato att baa bab baf bal ban bao bat bba bbb bbf bbl bbn bbo bbt bfa bfb bff bfl bfn bfo bft bla blb blf bll bln blo blt bna bnb bnf bnl bnn bno bnt boa bob bof bol bon boo bot bta btb btf btl btn bto btt faa fab faf fal fan fao fat fba fbb fbf fbl fbn fbo fbt ffa fff ffl ffn ffo fft fla flb flf fll fln flo flt fna fnb fnf fnl fnn fnt foa fob fof fol fon foo fot fta ftb ftf ftl ftn fto ftt la- laa lab laf lal lan lao lat lba lbb lbf lbl lbo lbt lfa lfb lff lfl lfn lfo lft lla llb llf lll lln llo llt lna lnb lnl lnn lno lnt loa lob lof lol lon loo lot lta ltb ltf ltl lto ltt naa nab naf nal nan nao nat nba nbb nbf nbl nbn nbo nbt nfa nfb nff nfl nfn nfo nft nla nlb nlf nll nln nlo nlt nna nnb nnf nnl nnn nno nnt no- noa nob nof nol non noo not nta ntb ntf ntn nto ntt oaa oab oaf oal oan oao oat ob- oba obb obf obl obn obo obt of- ofa ofb off ofl ofn ofo oft ola olb olf oll oln olo olt on- ona onb onf onl onn ono ont oo- ooa oob oof ool oon ooo oot ot- ota otb otf otl otn oto ott taa tab taf tal tan tao tat tba tbb tbf tbl tbn tbo tbt tfa tfb tff tfl tfn tfo tft tla tlf tll tln tlo tlt tna tnb tnf tnl tnn tno tnt to- toa tob tof tol ton too tot tta ttb ttf ttl ttn tto ttt