a-a a-b aaa aab aad aag aas ab- aba abb abd abg abs ad- ada adb add adg ads ag- aga agb agd agg ags as- asa asb asd asg ass baa bab bad bag bas bba bbb bbd bbg bbs bda bdb bdd bdg bds bga bgb bgd bgg bgs bsa bsb bsd bsg bss daa dab dad dag das dba dbb dbd dbg dbs dda ddb ddd ddg dds dga dgd dgg dgs dsa dsb dsd dsg dss g-d gaa gab gad gag gas gba gbd gbg gbs gda gdb gdd gds gga ggb ggd ggg ggs gsa gsb gsd gsg gss saa sab sad sag sas sba sbb sbd sbg sbs sda sdb sdd sdg sds sga sgb sgd sgg sgs ss- ssa ssb ssd ssg sss