tpaud ptaud tapud atpud patud aptud tpuad ptuad tupad utpad putad uptad taupd atupd tuapd utapd autpd uatpd pautd aputd puatd upatd auptd uaptd tpadu ptadu tapdu atpdu patdu aptdu tpdau ptdau tdpau dtpau pdtau dptau tadpu atdpu tdapu dtapu adtpu datpu padtu apdtu pdatu dpatu adptu daptu tpuda ptuda tupda utpda putda uptda tpdua ptdua tdpua dtpua pdtua dptua tudpa utdpa tdupa dtupa udtpa dutpa pudta updta pduta dputa udpta dupta taudp atudp tuadp utadp autdp uatdp tadup atdup tdaup dtaup adtup datup tudap utdap tduap dtuap udtap dutap audtp uadtp adutp dautp udatp duatp paudt apudt puadt upadt aupdt uapdt padut apdut pdaut dpaut adput daput pudat updat pduat dpuat udpat dupat audpt uadpt adupt daupt udapt duapt
Note: these 'words' (valid or invalid) are all the permutations of the word tpaud. These words are obtained by scrambling the letters in tpaud.