Complex sentence: The economy of Bécancour, once mainly agricultural, shifted towards heavy industry and manufacturing in the 1970s and 1980s, with the creation of an industrial park and a nuclear power plant (Gentilly Nuclear Generating Station) in the area.
Split into simpler sentences: The economy of Bécancour, once mainly agricultural, shifted towards heavy industry and manufacturing in the 1970s and 1980s. An industrial park and a nuclear power plant (Gentilly Nuclear Generating Station) were built in the area.