In this task, you are given a premise sentence. Your task is to write a new sentence by substituting the subject and object (i.e., the input's subject should be output's object and vice versa.). The generated sentence must be fluent and shouldn't change the voice (i.e., passive or active) of the input.

Q: The presidents mentioned the scientists .

A: The scientists mentioned the presidents .
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Q: The doctors called the author .

A: The author called the doctors .
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Q: The scientists that admired the presidents helped the doctor .

A:
The doctor helped the presidents .
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