-er eee eek eel eer eex eie eii eik eil eir eix eke eki ekl ekr ele eli elk ell elr elx ere eri erk erl err ex- exe exi exl exr exx ie- iee iei iek iel ier iex iie iii iil iir iix ike iki ikk ikl ikr ikx il- ile ili ilk ill ilr ilx ir- ire iri irk irl irr irx ixe ixi ixl ke- kee kei kek kel ker kex kie kii kik kil kir kix kke kki kkk kkl kkr kl- kli klr klx kri krk krl krr kxl lee lei lek lel ler lex lie lii lik lil lir lix lkl lkr lle lli llk lll llr lri lrk lrr lxi lxr lxx re- ree rei rek rel rer rex rie rii rik ril rir rix rke rkk rle rli rll rlr rri rrk rrl rrr rxr xee xel xer xex xie xii xix xke xkl xli xlr xrx xxi xxl xxx