prill rpill pirll iprll ripll irpll prlil rplil plril lpril rlpil lrpil pilrl iplrl plirl lpirl ilprl liprl rilpl irlpl rlipl lripl ilrpl lirpl prill rpill pirll iprll ripll irpll prlil rplil plril lpril rlpil lrpil pilrl iplrl plirl lpirl ilprl liprl rilpl irlpl rlipl lripl ilrpl lirpl prlli rplli plrli lprli rlpli lrpli prlli rplli plrli lprli rlpli lrpli pllri lplri pllri lplri llpri llpri rllpi lrlpi rllpi lrlpi llrpi llrpi pillr ipllr plilr lpilr ilplr liplr pillr ipllr plilr lpilr ilplr liplr pllir lplir pllir lplir llpir llpir illpr lilpr illpr lilpr llipr llipr rillp irllp rlilp lrilp ilrlp lirlp rillp irllp rlilp lrilp ilrlp lirlp rllip lrlip rllip lrlip llrip llrip illrp lilrp illrp lilrp llirp llirp
Note: these 'words' (valid or invalid) are all the permutations of the word prill. These words are obtained by scrambling the letters in prill.