Complex sentence: Mr. Mackey is making the kindergarten students perform a play about tooth decay and the importance of dental hygiene, and is furious when Ike, who is supposed to portray tooth decay, misses a rehearsal to watch the Canadian royal wedding.
Split into simpler sentences: Mr. Mackey is making the kindergarten students perform a play about tooth decay and the importance of dental hygiene. He is furious when Ike, who is supposed to portray tooth decay, misses a rehearsal to watch the Canadian royal wedding.