pists ipsts psits spits ispts sipts pitss iptss ptiss tpiss itpss tipss pstis sptis ptsis tpsis stpis tspis istps sitps itsps tisps stips tsips pisst ipsst psist spist ispst sipst pisst ipsst psist spist ispst sipst pssit spsit pssit spsit sspit sspit isspt sispt isspt sispt ssipt ssipt pitss iptss ptiss tpiss itpss tipss pists ipsts psits spits ispts sipts ptsis tpsis pstis sptis tspis stpis itsps tisps istps sitps tsips stips pstsi sptsi ptssi tpssi stpsi tspsi pssti spsti pssti spsti sspti sspti ptssi tpssi pstsi sptsi tspsi stpsi stspi tsspi sstpi sstpi tsspi stspi istsp sitsp itssp tissp stisp tsisp isstp sistp isstp sistp ssitp ssitp itssp tissp istsp sitsp tsisp stisp stsip tssip sstip sstip tssip stsip
Note: these 'words' (valid or invalid) are all the permutations of the word pists. These words are obtained by scrambling the letters in pists.