Complex sentence: On 1 March 1983 the Metro was extanded in the west to Kamppi, while the Sörnäinen station between Hakaniemi and Kulosaari was opened on 1 September 1984.
Split into simpler sentences: On 1 March 1983 the Metro was extanded in the west to Kamppi. The Sörnäinen station, between Hakaniemi and Kulosaari, was opened on 1 September 1984.