Complex sentence: Wendy and Kevin manage to save Ian before he is impaled, and a large wooden tile knocks over another plank which punctures a bag of saw dust blinding Erin, who falls back onto a nail gun that shoots several nails into her head.
Split into simpler sentences: Wendy and Kevin manage to save Ian before he is impaled, but a large wooden tile falls onto another plank, which is sent flying through the air, and punctures a bag of saw dust, blinding Erin. Erin falls back onto a nail gun that shoots several nails into her head.