-al a-a a-b aaa aab aae aaf aag aal ab- aba abb abe abf abg abl aea aeb aee aef aeg ael af- afa afb afe aff afg afl ag- aga agb age agf agg agl al- ala alb ale alf alg all baa bab bae baf bag bal bba bbb bbe bbf bbg bbl be- bea beb bee bef beg bel bfa bfb bfe bff bfg bfl bga bgb bge bgf bgg bgl bla blb ble blf blg bll eaa eab eae eaf eag eal eba ebb ebe ebf ebg ebl eea eeb eee eef eeg eel ef- efa efb efe eff efg efl ega egb ege egf egg egl ela elb ele elf elg ell faa fab fae faf fag fal fba fbb fbe fbf fbg fbl fea feb fee fef feg fel ffa ffe fff ffg ffl fga fgb fge fgf fgg fgl fla flb fle flf flg fll gaa gab gae gaf gag gal gba gbe gbf gbg gbl ge- gea geb gee gef geg gel gfa gfb gfe gff gfl gga ggb ggg gla glb gle glf glg gll la- laa lab lae laf lag lal lba lbb lbe lbf lbg lbl lea leb lee lef leg lel lfa lfb lfe lff lfg lfl lga lgb lge lgf lgg lgl lla llb lle llf llg lll