Original sentence: The Docklands Light Railway electric multiple units is a high-floor, bi-directional, single-articulated electrical multiple units used on the Docklands Light Railway, which serves the London Docklands region of London.The train has four doors on each side and each train normally composed of two 28m long cars, but there are plans to add a third car to the configuration
Edited sentence: The Docklands Light Railway rolling stock consists of high-floor, bi-directional, single-articulated electrical multiple units used in the London Docklands region of London.The trains have four doors on each side and each train is normally composed of two 28m long cars, though there are plans to add a third car to the configuration