Complex sentence: Pat is reluctant to participate in the dance contest under those conditions, goes outside to consult Nikki's letter, and notices that it also refers to "reading the signs," realizing that Tiffany wrote the letter.
Split into simpler sentences: Pat is reluctant to participate in the dance contest under those conditions. He goes outside to consult Nikki's letter, and notices that it also refers to "reading the signs," realizing that Tiffany wrote the letter.