a-a a-b aaa aab aad aam aar ab- aba abb abd abm abr ad- ada adb add adm adr ama amb amd amm amr ar- ara arb ard arm arr baa bab bad bam bar bba bbb bbd bbm bbr bda bdb bdd bdm bdr bma bmb bmd bmm bmr bra brb brd brm brr daa dab dad dam dar dba dbb dbd dbm dbr dda ddb ddd ddm ddr dma dmb dmd dmm dmr dra drb drd drm drr m-r maa mab mad mam mar mba mbb mbd mbm mbr mda mdb mdd mdm mdr mma mmb mmd mmm mmr mra mrb mrd mrm mrr ra- raa rab rad ram rar rba rbb rbd rbm rbr rda rdb rdd rdm rdr rma rmb rmd rmm rmr rra rrb rrd rrm rrr