Original sentence: Melbourne has an integrated public transport system known as Metlink, originally laid out late in the 19th century when trains and trams were the primary methods of travelling to the suburbs
Edited sentence: Melbourne has an integrated public transport system known as Metlink.Melbourne's public transport system was largely laid out late in the 19th century when trains and trams were the primary methods of travelling to the suburbs.Since this time, the extensive system has been maintained and modernised.While the public transport network is of considerable size, many of Melbourne's outlying suburbs still face transport difficulties