Complex sentence: The Orlando nightclub shooting, also known as the Orlando massacre, was a terrorist attack committed in the form of a mass shooting occurred at Pulse, a gay nightclub in Orlando, Florida on June 12th, 2016.
Split into simpler sentences: The Orlando nightclub shooting, also known as the Orlando massacre, was a terrorist attack committed in the form of a mass shooting. It occurred at Pulse, a gay nightclub in Orlando, Florida on June 12th, 2016.