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 stopped the bankers .

A: The bankers stopped the presidents .
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Q: The doctor who helped the tourists advised the professor .

A: The professor advised the tourists .
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Q: The scientists believed the author .

A:
The author believed the scientists .
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