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 tourist by the secretary introduced the students .

A: The students introduced the tourist .
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Q: The lawyers recognized the secretaries who introduced the actor .

A: The actor recognized the lawyers .
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Q: The professor helped the scientist next to the presidents .

A:
The presidents helped the professor .
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