Complex sentence: Jens Marni Hansen was one of the 10 artists who participated in Dansk Melodi Grand Prix, he performed the Rock song Gloria written by Sven Gudiksen, Johannes Jørgensen and Noah Halby.
Split into simpler sentences: Jens Marni Hansen was one of the 10 artists who participated in Dansk Melodi Grand Prix. He performed the Rock song "Gloria" written by Sven Gudiksen, Johannes Jørgensen, and Noah Halby.