Complex sentence: The Alum Rock-Santa Teresa line also contains parts of Tasman West extension opened in December 1999 from Tasman station to Baypointe station, and the first phase of the Tasman East extension opened in May 2001 between Baypointe and I-880/Milpitas stations.
Split into simpler sentences: The Alum Rock-Santa Teresa line also contains parts of Tasman West extension opened in December 1999 from Tasman station to Baypointe station. The first phase of the Tasman East extension opened in May 2001 between Baypointe and I-880/Milpitas stations.