Complex sentence: The Urban Institute is a Washington, D.C.-based think tank that carries out nonpartisan economic and social policy research, collects data, evaluates social programs, educates the public on key domestic issues, and provides advice and technical assistance to developing governments abroad.
Split into simpler sentences: The Urban Institute is a Washington, D.C.-based think tank which provides nonpartisan economic and social policy research. More specifically, it collects data, evaluates social programs, educates the public on key domestic issues, and provides advice and technical assistance to developing governments abroad.