Simplify the following text for a Grade 6 native English-speaking person.
Original: Helene Berg 's death in 1976 , just six months before the Metropolitan Opera was due to present the American premiere ( in a production by John Dexter ) , paved the way for a new completed version to be made by Friedrich Cerha .
Simplified: When Helene died in 1976 a man called Friedrich Cerha finished the opera , guessing what Berg might have written .