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 president encouraged the actors .
The actors encouraged the president .

The presidents helped the scientists .
The scientists helped the presidents .

The secretary by the tourist contacted the actors .

The tourist contacted the secretary .