Generate a sentence with the given entities and relation.
Relation: participant
Head Entity: Eurovision Song Contest 2006; Tail Entity: Tina Karol
Sentence: In 2007 Yurii Barybin was invited to hold a technical director and production manager positions for Tina Karol - singer , songwriter , Eurovision Song Contest 2006 Ukrainian representative .
Relation: participant
Head Entity1: ; Tail Entity2:
Sentence: