Complex sentence: David Klinghoffer is a controversial author and essayist, and a proponent of intelligent design who is a Senior Fellow of the Discovery Institute, the organization that is the driving force behind the intelligent design movement.
Split into simpler sentences: David Klinghoffer is a controversial author and essayist, and a proponent of intelligent design. He is a Senior Fellow of the Discovery Institute, the organization that is the driving force behind the intelligent design movement.