Complex sentence: The emergence of high school education in the Philippines islands, however, did not happen until 1910, caused by the rise in big businesses and technological advances in factories and the emergence of electrification that required skilled workers.
Split into simpler sentences: The emergence of high school education in the Philippines, however, did not happen until 1910. It was borne out of the rise in big businesses and technological advances in factories and the emergence of electrification, which required skilled workers.