eee eeo eep eet eev eex eo- eoe eoo eop eot ep- epe epo epp ept epx ete eto etp ett etv etx eve evo evp evt evv ex- exe exo exp ext exx oee oeo oep oet oex oo- ooo oop oot oov oox op- ope opo opp opt opv opx ot- ote oto otp ott otv ov- ove ovo ovp ovv ox- oxo oxt oxx p-p pee peo pep pet pev pex poe poo pop pot pov pox ppe ppo ppp ppt ppv ppx pt- pte pto ptp ptt ptv ptx pve pvo pvp pvt pvv pxe pxt t-x te- tee teo tep tet tev tex to- toe too top tot tov tox tpe tpo tpp tpt tpv tpx tte tto ttp ttt ttv ttx tve tvo tvp tvt tvx txe txt v-e vee veo vep vet vex voe voo vop vot vov vox vpe vpo vpp vpt vpx vte vto vtt vtv vtx vvo vvt vvv vxv xee xep xet xev xex xoo xop xot xov xox xpe xpo xpp xpt xtp xtv xtx xvt xxo xxp xxv xxx