Fill in the Blanks (Reading & Writing)

Port cities have historically grown wealthy by —servingservedservesto serve as gateways between inland producers and overseas markets. Their harbours attracted merchants, shipbuilders and dockworkers, and the resulting mix of cultures often made these cities more —cosmopolitancosmopolitanismcosmopolitecosmically than the interior regions they served. Even today, many major —metropolisesmetropolismetropolitanmetropolitans owe their prosperity to trade routes established centuries ago.