ebtpr betpr etbpr tebpr btepr tbepr ebptr beptr epbtr pebtr bpetr pbetr etpbr tepbr eptbr petbr tpebr ptebr btper tbper bpter pbter tpber ptber ebtrp betrp etbrp tebrp bterp tberp ebrtp bertp erbtp rebtp bretp rbetp etrbp terbp ertbp retbp trebp rtebp btrep tbrep brtep rbtep trbep rtbep ebprt beprt epbrt pebrt bpert pbert ebrpt berpt erbpt rebpt brept rbept eprbt perbt erpbt repbt prebt rpebt bpret pbret brpet rbpet prbet rpbet etprb teprb eptrb petrb tperb pterb etrpb terpb ertpb retpb trepb rtepb eprtb pertb erptb reptb pretb rpetb tpreb ptreb trpeb rtpeb prteb rpteb btpre tbpre bptre pbtre tpbre ptbre btrpe tbrpe brtpe rbtpe trbpe rtbpe bprte pbrte brpte rbpte prbte rpbte tprbe ptrbe trpbe rtpbe prtbe rptbe
Note: these 'words' (valid or invalid) are all the permutations of the word ebtpr. These words are obtained by scrambling the letters in ebtpr.