wyfl ywfl wfyl fwyl yfwl fywl wylf ywlf wlyf lwyf ylwf lywf wfly fwly wlfy lwfy flwy lfwy yflw fylw ylfw lyfw flyw lfyw
Note: these 'words' (valid or invalid) are all the permutations of the word wyfl. These words are obtained by scrambling the letters in wyfl.