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Is there any grammer mistake or ununderstood part of the text below.

thanks in advance

İstanbul Folk Ensemble was established in 2008. Musical structure of the orchcstrate includes the original compositions that belonged to Turkish composers, and the authentic Works, which come out of Classical Turkish Music. It also contains classical, modal and modern compostions and orchestrate arrangments that are created after being inspired of authentic works belonged to the Turkish Folklor Music.
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The İstanbul Folk Ensemble was established in 2008. Musical structure The repertoire of the orchestra includes the original compositions of that belonged to Turkish composers, and the authentic works, which come out of classical Turkish music. It also contains classical, modal and modern compostions and orchestral arrangments that are created after being inspired of by authentic works based on belonged to the Turkish folkloric music.
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The İstanbul Folk Ensemble was established in 2008. The musical structure of the orchestra is based on the original compositions by Turkish composers and their authentic works, which are of Classical Turkish Music. It is also based on classical, modal (what is this?) and modern compositions, and orchestra arrangments that were created when inspired by the authentic works of a Turkish Folklore Music origin.

Students: Are you brave enough to let our tutors analyse your pronunciation?
"The İstanbul Folk Ensemble was established in 2008. The group's repertoire includes classical, modal and modern compositions and arrangements inspired by Turkish folk music. It also includes original compositions of Turkish composers and authentic works of classical Turkish music."

I hope I understood your meaning correctly.

I put the sentence about folk music first because I assume from the name that the Ensemble's main focus is on folk music.

I don't really understand the difference between "original compositions of Turkish composers" and "authentic works of classical Turkish music". Aren't the compositions of Turkish composers also authentic works of classical Turkish music?

Edit: Sorry, I meant to specifically mention that I changed "musical structure" to "repertoire". An ensemble's "musical structure" can't "include" or "contain" compositions or musical works. I'm assuming that you're talking about the pieces of music they play (their "repertoire").
 AlpheccaStars's reply was promoted to an answer.