-al -ol a-a a-b a-t aaa aab aal aao aat aax ab- aba abb abl abo abt abx al- ala alb all alo alt alx aoa aob aol aoo aot aox at- ata atb atl ato att atx ax- axa axl axo axt axx baa bab bal bao bat bax bba bbb bbl bbo bbt bbx bla blb bll blo blt blx boa bob bol boo bot box bta btb btl bto btt btx bxb bxl bxo bxx la- laa lab lal lao lat lax lba lbb lbl lbo lbt lbx lla llb lll llo llt loa lob lol loo lot lox lta ltb ltl lto ltt ltx lxo lxx oaa oab oal oao oat oax ob- oba obb obl obo obt obx ola olb oll olo olt oo- ooa oob ool ooo oot oox ot- ota otb otl oto ott ox- oxa oxb oxo oxt oxx t-x taa tab tal tao tat tax tba tbb tbl tbo tbt tla tll tlo tlt tlx to- toa tob tol too tot tox tta ttb ttl tto ttt ttx txl txt xaa xal xat xbl xbx xla xlb xlt xoa xoo xot xox xtx xxl xxo xxx