Simplify the following text for a Grade 3 native English-speaking person.
Original: In music , valkyries play a major role in `` Die WalkÃ 1\/4 re '' ( 1870 ) by Richard Wagner ( the second of the four operas that comprise Der Ring des Nibelungen ) , in which the `` Ride of the Valkyries '' begins Act III .
Simplified: The music for the opening of Act Three of Die WalkÃ 1\/4 re is very famous . It is called the Ride of the Valkyries .