eee eeo eep ees eet eie eii eio eip eis eit eo- eoe eoi eoo eop eos eot ep- epe epi epo epp eps ept es- ese esi eso esp ess est ete eti eto etp ets ett ie- iee iei iep ies iet iie iii iio iip iis iit io- ioe ioi ioo iop ios iot ipe ipi ipo ipp ips ipt is- ise isi iso isp iss ist ite iti ito itp its itt o-i oee oei oeo oep oes oet oie oii oio oip ois oit oo- ooi ooo oop oos oot op- ope opi opo opp ops opt os- ose osi oso osp oss ost ot- ote oti oto otp ots ott p-p pee pei peo pep pes pet pie pii pio pip pis pit poe poi poo pop pos pot ppe ppi ppo ppp pps ppt ps- pse psi pso psp pss pst pt- pte pti pto ptp pts ptt se- see sei seo sep ses set sie sii sio sip sis sit soe soi soo sop sos sot spe spi spo spp sps spt ss- sse ssi sso ssp sss sst ste sti sto stp sts stt te- tee tei teo tep tes tet tie tii tio tip tis tit to- toe toi too top tos tot tpe tpi tpo tpp tps tpt tse tsi tso tsp tss tst tte tti tto ttp tts ttt