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.

The athlete mentioned the artist .
The artist mentioned the athlete .

The banker stopped the athletes that the actor called .
The athletes stopped the banker .

The president mentioned the professor behind the artist .

The artist mentioned the president .