-al a-a a-c aaa aac aae aal aax ac- aca acc ace acl acx aea aec aee ael aex al- ala alc ale all alx ax- axa axe axl axx c-- caa cac cae cal cax cca ccc cce ccl ccx ce- cea cec cee cel cex cl- cla clc cle cll clx cxc cxl cxx eaa eac eae eal eax ec- eca ecc ece ecl ecx eea eec eee eel eex ela elc ele ell elx ex- exa exc exe exl exx la- laa lac lae lal lax lca lcc lce lcl lcx lea lec lee lel lex lla llc lle lll lxc lxx xaa xac xal xcl xcx xee xel xex xla xxl xxx