pings ipngs pnigs npigs inpgs nipgs pigns ipgns pgins gpins igpns gipns pngis npgis pgnis gpnis ngpis gnpis ingps nigps ignps ginps ngips gnips pinsg ipnsg pnisg npisg inpsg nipsg pisng ipsng psing sping ispng sipng pnsig npsig psnig spnig nspig snpig inspg nispg isnpg sinpg nsipg snipg pigsn ipgsn pgisn gpisn igpsn gipsn pisgn ipsgn psign spign ispgn sipgn pgsin gpsin psgin spgin gspin sgpin igspn gispn isgpn sigpn gsipn sgipn pngsi npgsi pgnsi gpnsi ngpsi gnpsi pnsgi npsgi psngi spngi nspgi snpgi pgsni gpsni psgni spgni gspni sgpni ngspi gnspi nsgpi sngpi gsnpi sgnpi ingsp nigsp ignsp ginsp ngisp gnisp insgp nisgp isngp singp nsigp snigp igsnp gisnp isgnp signp gsinp sginp ngsip gnsip nsgip sngip gsnip sgnip
Note: these 'words' (valid or invalid) are all the permutations of the word pings. These words are obtained by scrambling the letters in pings.