extst xetst etxst texst xtest txest exstt xestt esxtt sextt xsett sxett etsxt tesxt estxt setxt tsext stext xtset txset xstet sxtet tsxet stxet extts xetts etxts texts xtets txets extts xetts etxts texts xtets txets ettxs tetxs ettxs tetxs ttexs ttexs xttes txtes xttes txtes ttxes ttxes exstt xestt esxtt sextt xsett sxett extst xetst etxst texst xtest txest estxt setxt etsxt tesxt stext tsext xstet sxtet xtset txset stxet tsxet etstx testx esttx settx tsetx stetx ettsx tetsx ettsx tetsx ttesx ttesx esttx settx etstx testx stetx tsetx tstex sttex ttsex ttsex sttex tstex xtste txste xstte sxtte tsxte stxte xttse txtse xttse txtse ttxse ttxse xstte sxtte xtste txste stxte tsxte tstxe sttxe ttsxe ttsxe sttxe tstxe
Note: these 'words' (valid or invalid) are all the permutations of the word extst. These words are obtained by scrambling the letters in extst.