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 president called the secretary that helped the scientist .

SOLUTION: The scientist called the president .

PROBLEM: The doctors stopped the presidents next to the lawyers .

SOLUTION: The presidents stopped the lawyers .

PROBLEM: The president contacted the lawyer that believed the actors .

SOLUTION:
The actors contacted the president .

