The document contrasts active and passive voice in sentences. Active voice follows the formula of subject + verb + object and positions the subject as the performer of the action, such as "The Police arrested the thief." Passive voice follows the formula of object + helping verb + past participle + by + subject and positions the object as the topic of the sentence, such as "The thief was arrested by the Police." Examples are provided to illustrate the difference between active and passive constructions.