An internet meme from 2003 (read more here) asserted that readers are relatively insensitive to letter order in words, so long as the first and last letters are unchanged.
Given a string of words s, take each word in turn and reverse the order of letters 2 through n-1, where n is the length of the words. Non-alphabetic characters should remain in place.
sIn = 'hello'
sOut = 'hlleo'
sIn = 'This is the first time I have used MATLAB.'
sOut = 'Tihs is the fsrit tmie I hvae uesd MALTAB.'