ylwb lywb ywlb wylb lwyb wlyb ylbw lybw yblw bylw lbyw blyw ywbl wybl ybwl bywl wbyl bwyl lwby wlby lbwy blwy wbly bwly
Note: these 'words' (valid or invalid) are all the permutations of the word ylwb. These words are obtained by scrambling the letters in ylwb.