calks aclks claks lcaks alcks lacks cakls ackls ckals kcals akcls kacls clkas lckas cklas kclas lkcas klcas alkcs lakcs aklcs kalcs lkacs klacs calsk aclsk clask lcask alcsk lacsk caslk acslk csalk scalk asclk saclk clsak lcsak cslak sclak lscak slcak alsck lasck aslck salck lsack slack caksl acksl ckasl kcasl akcsl kacsl caskl acskl csakl scakl asckl sackl cksal kcsal cskal sckal kscal skcal akscl kascl askcl sakcl ksacl skacl clksa lcksa cklsa kclsa lkcsa klcsa clska lcska cslka sclka lscka slcka cksla kcsla cskla sckla kscla skcla lksca klsca lskca slkca kslca sklca alksc laksc aklsc kalsc lkasc klasc alskc laskc aslkc salkc lsakc slakc akslc kaslc asklc saklc ksalc skalc lksac klsac lskac slkac kslac sklac
Note: these 'words' (valid or invalid) are all the permutations of the word calks. These words are obtained by scrambling the letters in calks.