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.

[Q]: An advance on his grenades was what he wanted so he had said .
[A]: Changed


[Q]: The invitation into the computer room was the straw that broke the camel 's back .
[A]: Original


[Q]: It wasn 't my best athlete , but it was the first thing to come to mind .
[A]:
Changed