-al a-a a-b a-t aaa aab aaf aag aal aat ab- aba abb abf abg abl abt af- afa afb aff afg afl aft ag- aga agb agf agg agl agt al- ala alb alf alg all alt at- ata atb atf atg atl att baa bab baf bag bal bat bba bbb bbf bbg bbl bbt bfa bfb bff bfg bfl bft bga bgb bgf bgg bgl bgt bla blb blf blg bll blt bta btb btf btg btl btt faa fab faf fag fal fat fba fbb fbf fbg fbl fbt ffa fff ffg ffl fft fga fgb fgf fgg fgl fgt fla flb flf flg fll flt fta ftb ftf ftg ftl ftt gaa gab gaf gag gal gat gba gbf gbg gbl gbt gfa gfb gff gfl gft gga ggb ggg ggt gla glb glf glg gll glt gta gtb gtf gtg gtl gtt la- laa lab laf lag lal lat lba lbb lbf lbg lbl lbt lfa lfb lff lfg lfl lft lga lgb lgf lgg lgl lgt lla llb llf llg lll llt lta ltb ltf ltg ltl ltt taa tab taf tag tal tat tba tbb tbf tbg tbl tbt tfa tfb tff tfg tfl tft tga tgb tgf tgg tgl tgt tla tlf tlg tll tlt tta ttb ttf ttg ttl ttt