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 actors introduced the authors .
The authors introduced the actors .

The doctors contacted the authors .
The authors contacted the doctors .

The scientists thanked the senators who mentioned the professor .

The senators thanked the scientists .