yhats hyats yahts ayhts hayts ahyts yhtas hytas ythas tyhas htyas thyas yaths ayths ytahs tyahs atyhs tayhs hatys ahtys htays thays athys tahys yhast hyast yahst ayhst hayst ahyst yhsat hysat yshat syhat hsyat shyat yasht aysht ysaht syaht asyht sayht hasyt ahsyt hsayt shayt ashyt sahyt yhtsa hytsa ythsa tyhsa htysa thysa yhsta hysta yshta syhta hsyta shyta ytsha tysha ystha sytha tsyha styha htsya thsya hstya shtya tshya sthya yatsh aytsh ytash tyash atysh taysh yasth aysth ysath syath asyth sayth ytsah tysah ystah sytah tsyah styah atsyh tasyh astyh satyh tsayh stayh hatsy ahtsy htasy thasy athsy tahsy hasty ahsty hsaty shaty ashty sahty htsay thsay hstay shtay tshay sthay atshy tashy asthy sathy tsahy stahy
Note: these 'words' (valid or invalid) are all the permutations of the word yhats. These words are obtained by scrambling the letters in yhats.