eeee eete eext eiei eier eipr eire eiti eitr epee eper epi- epie epip epit epix eppp eprp epte epxp er-x erei erer eret erie erit erpe erre etee eter etix etre ette etti exer exit expr expt exrx exte extr ieet ieie iere ieri iett iiie iiii iiit iitr iitt iper ipet ipex ipie ipix ippr ipri ipxe iree irer irex iri- irie irip irix irpe irre irri irte irti irtp itep iter itet itex itie itri ixxi peep peer peet peip peir peit pepe pepi per- pere peri perp perr pert pete peti petr pett piep pier piet piip pipe pipi pipp pire piri pirr pite piti pitr pitt pitx pixx pper ppie pppp pptt pre- pree prep pret prex pri- prie prii prix prri prti prtp prtr pter reep reet reii reir reit repe repi repp repr rept rere reri rert rete reti retr rett rexx riep rier riet riex ripe ripi ripp ripr ript rire riri rite riti ritt rixe rpet rpii rpix rrrr rtee rtei rtex rttp teer teet teie teip teir tepe tepi tepp ter- tere teri terp terr tete teti tetr tett tetx text tie- tiee tiei tiep tier tiet tiit tip- tipe tipi tipp tipt tire tiri tirr tite titi titp titt tixt tper tpir tppp tppr tpte tptp tptr tre- tree trei tret trex tri- trie trip trit trix trpe trpp trte trtr tter tttt txii txtr xeer xer- xert xexe xiii xipe xixi xper xrep xtep xtie xxii xxix xxxi xxxx