rings irngs rnigs nrigs inrgs nirgs rigns irgns rgins grins igrns girns rngis nrgis rgnis grnis ngris gnris ingrs nigrs ignrs ginrs ngirs gnirs rinsg irnsg rnisg nrisg inrsg nirsg risng irsng rsing sring isrng sirng rnsig nrsig rsnig srnig nsrig snrig insrg nisrg isnrg sinrg nsirg snirg rigsn irgsn rgisn grisn igrsn girsn risgn irsgn rsign srign isrgn sirgn rgsin grsin rsgin srgin gsrin sgrin igsrn gisrn isgrn sigrn gsirn sgirn rngsi nrgsi rgnsi grnsi ngrsi gnrsi rnsgi nrsgi rsngi srngi nsrgi snrgi rgsni grsni rsgni srgni gsrni sgrni ngsri gnsri nsgri sngri gsnri sgnri ingsr nigsr ignsr ginsr ngisr gnisr insgr nisgr isngr singr nsigr snigr igsnr gisnr isgnr signr gsinr sginr ngsir gnsir nsgir sngir gsnir sgnir
Note: these 'words' (valid or invalid) are all the permutations of the word rings. These words are obtained by scrambling the letters in rings.