-er eee eem eer eet eex eie eii eim eir eit eix em- eme emi emm emr emt emx ere eri erm err ert ete eti etm etr ett etx ex- exe exi exr ext exx ie- iee iei iem ier iet iex iie iii iim iir iit iix im- ime imi imm imt imx ir- ire iri irm irr irt irx ite iti itm itt itx ixe ixi m-r mee mei mem mer met mex mi- mie mii mim mir mit mix mme mmi mmm mmr mmt mmx mre mri mrm mrr mrt mrx mte mti mtm mtr mtt mtx mxi mxr re- ree rei rem rer ret rex rie rii rim rir rit rix rme rmi rmm rmr rmt rmx rri rrm rrr rrt rte rti rtm rtr rtt rtx rxr t-x te- tee tei tem ter tet tex tie tii tim tir tit tix tme tmi tmm tmr tmt tmx tre tri trm trr trt trx tte tti ttm ttr ttt ttx txe txi txt xee xem xer xet xex xie xii xit xix xmi xmm xmr xmt xmx xrt xrx xti xtm xtr xtx xxi xxx