Original sentence: The Union of Soviet Socialist Republics (USSR or Soviet Union; Soyuz Sovetskikh Sotsialisticheskikh Respublik, SSSR written in the Cyrillic alphabet as СССР) was a communist-ruled union with a single party system that existed from 1922 until 1991
Edited sentence: The Union of Soviet Socialist Republics (USSR or Soviet Union; Soyuz Sovetskikh Sotsialisticheskikh Respublik, SSSR written in the Cyrillic alphabet as СССР) was a communist-ruled union with a totalitarian regime that existed from 1922 until 1991