Simplify the following text for a Grade 9 native English-speaking person.
Original: Under the privatised railway system in Great Britain , the franchise was operated by NXEC Trains Limited , a subsidiary of National Express Group , who operated the franchise in return for payments being made to the Department for Transport .
Simplified: NXEC Trains Ltd is a subsidiary of National Express Group . National Express took over the franchise from the Great North Eastern Railway ( GNER ) .