Simplify the following text for a Grade 8 native English-speaking person.
Original: The directors and guards of the Western powers ( France , Britain , and the United States ) , repeatedly voiced opposition to many of the stricter measures and made near-constant protest about them to their superiors throughout the prison 's existence , but they were invariably vetoed by the Soviet Union , which favored a tougher approach .
Simplified: The directors and guards of the Western powers ( France , Britain , and the United States ) , often complained about many of the stricter measures . The complaints were often vetoed by the Soviet Union , because it thought the rules should be stricter .