Complex sentence: The monopoly of the state owned railway operator has to some extent been cancelled, but the major national passenger train operator, SJ AB (usually just called SJ), and the cargo transport operator, Green Cargo, are both fully owned by the state.
Split into simpler sentences: The monopoly of the state owned railway operator has to some extent been cancelled. Major national passenger train operators SJ AB (usually just called SJ), and the cargo transport operator, Green Cargo, are both fully owned by the state.