Complex sentence: The Asker Line was built in two stages: the first from Asker to Sandvika was built from 2001 to 2005, and the second stage, from Sandvika to Lysaker, between 2007 and 2011.
Split into simpler sentences: The Asker Line was built in two stages: the first, from Asker to Sandvika, was constructed between 2001 and 2005. The second stage, from Sandvika to Lysaker, was constructed between 2007 and 2011.