-al a-a a-b a-c a-t aaa aab aac aae aal aat aax ab- aba abb abc abe abl abt abx ac- aca acb acc ace acl act acx aea aeb aec aee ael aet aex al- ala alb alc ale all alt alx at- ata atb atc ate atl att atx ax- axa axe axl axt axx baa bab bac bae bal bat bax bba bbb bbc bbe bbl bbt bbx bca bcb bcc bce bcl bct bcx be- bea beb bec bee bel bet bex bla blb blc ble bll blt blx bta btb btc bte btl btt btx bxb bxl bxx c-- caa cab cac cae cal cat cax cba cbb cbc cbe cbl cbt cbx cca ccb ccc cce ccl cct ccx ce- cea ceb cec cee cel cet cex cl- cla clb clc cle cll clt clx cta ctb ctc cte ctl ctt ctx cxc cxl cxt cxx eaa eab eac eae eal eat eax eba ebb ebc ebe ebl ebt ebx ec- eca ecb ecc ece ecl ect ecx eea eeb eec eee eel eet eex ela elb elc ele ell elt elx eta etb etc ete etl ett etx ex- exa exc exe exl ext exx la- laa lab lac lae lal lat lax lba lbb lbc lbe lbl lbt lbx lca lcb lcc lce lcl lct lcx lea leb lec lee lel let lex lla llb llc lle lll llt lta ltb ltc lte ltl ltt ltx lxc lxx t-x taa tab tac tae tal tat tax tba tbb tbc tbe tbl tbt tca tcb tcc tce tcl tct tcx te- tea teb tec tee tel tet tex tla tlc tle tll tlt tlx tta ttb ttc tte ttl ttt ttx txe txl txt xaa xac xal xat xbc xbe xbl xbx xcb xcl xcx xee xel xet xex xla xlb xlt xtc xtx xxl xxx