In this task, you are given a sentence. You must judge whether a single noun or verb has been replaced with another word with the same part of speech. The inversion would result in the sentence sounding unnatural, So unnatural sentences will be considered changed. Label the instances as "Original" or "Changed" based on your judgment.

Example Input: " Let 's mimic a truce .
Example Output: Changed

Example Input: " He 's made out of old iron and horseshoe nails . "
Example Output: Original

Example Input: You aren 't undead , or the walking dead , and Buffy isn 't a reliable anatomical terminology .
Example Output:
Changed