shall hsall sahll ashll hasll ahsll shlal hslal slhal lshal hlsal lhsal salhl aslhl slahl lsahl alshl lashl halsl ahlsl hlasl lhasl alhsl lahsl shall hsall sahll ashll hasll ahsll shlal hslal slhal lshal hlsal lhsal salhl aslhl slahl lsahl alshl lashl halsl ahlsl hlasl lhasl alhsl lahsl shlla hslla slhla lshla hlsla lhsla shlla hslla slhla lshla hlsla lhsla sllha lslha sllha lslha llsha llsha hllsa lhlsa hllsa lhlsa llhsa llhsa sallh asllh slalh lsalh alslh laslh sallh asllh slalh lsalh alslh laslh sllah lslah sllah lslah llsah llsah allsh lalsh allsh lalsh llash llash halls ahlls hlals lhals alhls lahls halls ahlls hlals lhals alhls lahls hllas lhlas hllas lhlas llhas llhas allhs lalhs allhs lalhs llahs llahs
Note: these 'words' (valid or invalid) are all the permutations of the word shall. These words are obtained by scrambling the letters in shall.