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 helped the scientists .

A: The scientists helped the presidents .
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Q: The actors introduced the secretaries .

A: The secretaries introduced the actors .
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Q: The professor encouraged the senators that the actors helped .

A:
The senators encouraged the actors .
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