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 tourists thanked the doctor .

SOLUTION: The doctor thanked the tourists .

PROBLEM: The senators contacted the scientist .

SOLUTION: The scientist contacted the senators .

PROBLEM: The actor called the professors .

SOLUTION:
The professors called the actor .