-er ddd dde ddi ddk ddr ddx de- ded dee dei dek der dex di- did die dii dik dir dix dke dki dkk dkr dkx drd dre dri drk drr drx dxd dxi dxr dxx ed- edd ede edi edk edr edx eed eee eek eer eex eid eie eii eik eir eix ekd eke eki ekr erd ere eri erk err ex- exd exe exi exr exx i-d idd ide idi idk idr idx ie- ied iee iei iek ier iex iid iie iii iir iix ike iki ikk ikr ikx ir- ird ire iri irk irr irx ixe ixi kde kdk kdr kdx ke- ked kee kei kek ker kex kid kie kii kik kir kix kke kki kkk kkr krd kri krk krr rdd rde rdi rdr rdx re- red ree rei rek rer rex rid rie rii rik rir rix rke rkk rrd rri rrk rrr rxr xde xdi xdk xdr xed xee xer xex xie xii xix xke xrd xrx xxi xxx