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.
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Question: The tourist called the doctor .

Answer: The doctor called the tourist .


Question: The professors contacted the judges .

Answer: The judges contacted the professors .


Question: The scientists helped the presidents .

Answer:
The presidents helped the scientists .