-al a-a a-b aaa aab aae aaf aak aal aan ab- aba abb abe abf abk abl abn aea aeb aee aef aek ael aen af- afa afb afe aff afk afl afn aka akb ake akk akl akn al- ala alb ale alf alk all aln an- ana anb ane anf ank anl ann baa bab bae baf bak bal ban bba bbb bbe bbf bbk bbl bbn be- bea beb bee bef bek bel ben bfa bfb bfe bff bfl bfn bka bkb bke bkf bkk bkl bkn bla blb ble blf blk bll bln bna bnb bne bnf bnk bnl bnn eaa eab eae eaf eak eal ean eba ebb ebe ebf ebk ebl ebn eea eeb eee eef eek eel een ef- efa efb efe eff efl eka ekb eke ekf ekl ela elb ele elf elk ell eln en- ena enb ene enf enk enl enn faa fab fae faf fak fal fan fba fbb fbe fbf fbk fbl fbn fea feb fee fef fek fel fen ffa ffe fff ffk ffl ffn fka fkb fkf fkk fkl fla flb fle flf fll fln fna fnb fne fnf fnk fnl fnn ka- kaa kab kae kaf kak kal kan kba kbb kbe kbf kbk kbl kbn ke- kea keb kee kef kek kel ken kfa kff kkb kke kkk kkl kkn kl- kla klb klf kn- kna kne knf knk knl knn la- laa lab lae laf lak lal lan lba lbb lbe lbf lbk lbl lea leb lee lef lek lel len lfa lfb lfe lff lfk lfl lfn lka lkb lkl lla llb lle llf llk lll lln lna lnb lne lnk lnl lnn naa nab nae naf nak nal nan nba nbb nbe nbf nbk nbl nbn ne- nea neb nee nef nek nel nen nfa nfb nfe nff nfk nfl nfn nka nke nkf nkk nkn nla nlb nle nlf nlk nll nln nna nnb nne nnf nnk nnl nnn