-er a-a a-i aaa aae aai aao aap aar aax aea aee aei aeo aep aer aex ai- aia aie aii aio aip air aix aoa aoe aoi aoo aop aor aox ap- apa ape api apo app apr apx ar- ara are ari aro arp arr arx ax- axa axe axi axo axp axr axx eaa eae eai eao eap ear eax eea eee eeo eep eer eex eia eie eii eio eip eir eix eo- eoa eoe eoi eoo eop eor ep- epa epe epi epo epp epr epx era ere eri ero erp err ex- exa exe exi exo exp exr exx ia- iaa iae iai iao iap iar ie- iea iee iei iep ier iex iia iie iii iio iip iir iix io- ioa ioe ioi ioo iop ior ipa ipe ipi ipo ipp ipr ipx ir- ira ire iri iro irp irr irx ixe ixi o-i oaa oae oai oao oap oar oax oea oee oei oeo oep oer oex oia oie oii oio oip oir oo- ooa ooi ooo oop oor oox op- opa ope opi opo opp opr opx or- ora ore ori oro orp orr orx ox- oxa oxi oxo oxx p-p paa pae pai pao pap par pax pea pee pei peo pep per pex pia pie pii pio pip pir pix poa poe poi poo pop por pox ppa ppe ppi ppo ppp ppr ppx pra pre pri pro prp prr prx pxe pxr ra- raa rae rai rao rap rar rax re- rea ree rei reo rep rer rex ria rie rii rio rip rir rix roa roe roi roo rop ror rox rpa rpe rpi rpo rpp rpr rpx rra rri rrp rrr rxp rxr xaa xap xar xee xep xer xex xia xie xii xio xix xoa xoi xoo xop xor xox xpa xpe xpo xpp xrx xxi xxo xxp xxx