echst cehst ehcst hecst chest hcest ecsht cesht escht secht cseht sceht ehsct hesct eshct sehct hsect shect chset hcset cshet schet hscet shcet echts cehts ehcts hects chets hcets ecths ceths etchs techs ctehs tcehs ehtcs hetcs ethcs tehcs htecs thecs chtes hctes cthes tches htces thces ecsth cesth escth secth cseth sceth ectsh cetsh etcsh tecsh ctesh tcesh estch setch etsch tesch stech tsech csteh scteh ctseh tcseh stceh tsceh ehstc hestc eshtc sehtc hsetc shetc ehtsc hetsc ethsc tehsc htesc thesc esthc sethc etshc teshc stehc tsehc hstec shtec htsec thsec sthec tshec chste hcste cshte schte hscte shcte chtse hctse cthse tchse htcse thcse csthe scthe ctshe tcshe stche tsche hstce shtce htsce thsce sthce tshce
Note: these 'words' (valid or invalid) are all the permutations of the word echst. These words are obtained by scrambling the letters in echst.