Simplify the following text for a Grade 9 native English-speaking person.
Original: The Parthenon Marbles , known also as the Elgin Marbles , are a collection of classical Greek marble sculptures ( mostly by Phidias and his pupils ) , inscriptions and architectural members that originally were part of the Parthenon and other buildings on the Acropolis of Athens .
Simplified: The Elgin Marbles , sometimes called the Acropolis Marbles , are a series of ancient Greek sculptures made from marble . They were originally part of the Parthenon temple in Athens but they were taken away by Thomas Bruce , 7th Earl of Elgin in the early 1800s .