Complex sentence: Several bombers in the second and third wave attacked the burning school, thinking it was their target, and as a result 86 schoolchildren died in the school, along with 18 adults, including many nuns.
Split into simpler sentences: Several bombers in the second and third wave attacked the burning school, thinking it was their target. As a result 86 schoolchildren died in the school, along with 18 adults, including many nuns.