Complex sentence: In 2006, it expanded from 10,000 to, adding spaces at 519 and 533 West 19th Street, allowing the gallery to mount three independent, full-scale exhibitions simultaneously.
Split into simpler sentences: In 2006, it expanded from 10,000 to, adding spaces at 519 and 533 West 19th Street. This allows the gallery to mount three independent full-scale exhibitions simultaneously.