TASK DEFINITION: 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.
PROBLEM: The author saw the actor .

SOLUTION: The actor saw the author .

PROBLEM: The scientists advised the author .

SOLUTION: The author advised the scientists .

PROBLEM: The secretary that the actors recognized believed the professor .

SOLUTION:
The professor believed the actors .