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 professor supported the actor behind the scientist .
The scientist supported the professor .

The actors called the presidents .
The presidents called the actors .

The doctors that the scientist helped mentioned the senator .

The senator mentioned the doctors .