Complex sentence: The Bow is a 158,000-square-metre (1.7 million sq ft) office building currently under construction for the headquarters of EnCana Corporation and Cenovus Energy, which was spun off from Encana in late 2009.
Split into simpler sentences: The Bow is a 158,000-square-metre (1.7 million sq ft) office building currently under construction for the headquarters of EnCana Corporation. It will also be occupied by Cenovus, which was spun off from Encana in late 2009.