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 scientist thanked the senators behind the doctors .
The doctors thanked the scientist .

The doctors contacted the bankers behind the professors .
The professors contacted the doctors .

The artists near the author mentioned the tourists .

The tourists mentioned the author .