Simplify the following text for a Grade 9 native English-speaking person.
Original: The early period of Marathi theater was dominated by playwrights like Kolhatkar , Khadilkar , Deval , Gadkari and Kirloskar who enriched the Marathi theater for about half a century with excellent musical plays known as Sangeet Naatak .
Simplified: Early Marathi theater had important playwrights ( people who write plays ) like Kolhatkar , Khadilkar , Deval , Gadkari and Kirloskar . They wrote musical plays called Sangeet Naatak .