schwa cshwa shcwa hscwa chswa hcswa scwha cswha swcha wscha cwsha wcsha shwca hswca swhca wshca hwsca whsca chwsa hcwsa cwhsa wchsa hwcsa whcsa schaw cshaw shcaw hscaw chsaw hcsaw scahw csahw sachw aschw cashw acshw shacw hsacw sahcw ashcw hascw ahscw chasw hcasw cahsw achsw hacsw ahcsw scwah cswah swcah wscah cwsah wcsah scawh csawh sacwh ascwh caswh acswh swach wsach sawch aswch wasch awsch cwash wcash cawsh acwsh wacsh awcsh shwac hswac swhac wshac hwsac whsac shawc hsawc sahwc ashwc haswc ahswc swahc wsahc sawhc aswhc washc awshc hwasc whasc hawsc ahwsc wahsc awhsc chwas hcwas cwhas wchas hwcas whcas chaws hcaws cahws achws hacws ahcws cwahs wcahs cawhs acwhs wachs awchs hwacs whacs hawcs ahwcs wahcs awhcs
Note: these 'words' (valid or invalid) are all the permutations of the word schwa. These words are obtained by scrambling the letters in schwa.