Simplify the following text for a Grade 6 native English-speaking person.
Original: The opera has been adapted for motion pictures on several occasions , most notably in a 1953 production which starred Lois Maxwell and Sophia Loren , and a 1987 Swedish production .
Simplified: The opera has been adapted for movies several times , e.g. in a film made in 1953 starring Lois Maxwell and Sophia Loren , and a Swedish production in 1987 .