How is the Eastern Catholic Church similar to the Roman Catholic Church?

Catholic Answer It's just Catholic, not Roman Catholic. Roman is an epithet first commonly used in England after the protestant revolt to describe the Catholic Church. It is never used by the official Catholic Church.

The Eastern Catholic Church is identical to the Catholic Church, they only differ in Rite. The Catholic Church includes all Rites. The person asking the question is using "Roman Catholic Church" which probably means that they are referring to the Latin Rite of the Church, but the Eastern Rites are every bit as much Catholic Church as the Latin Rite.