Complex sentence: Nerman graduated from the Norrköping gymnasium (secondary school) in 1903 at the age of 17, and on the graduation day he took his school bible and tossed it in the Motala ström river.
Split into simpler sentences: Nerman graduated from the Norrköping gymnasium (secondary school) in 1903 at the age of 17. On the graduation day he took his school bible and tossed it in the Motala ström river.