Complex sentence: In the early 20th century, renovations were made to the Paddock Building, while the arcade received a translucent steel and wire glass dropped ceiling between its second and third stories, which still allowed light to filter in from its glass roof.
Split into simpler sentences: In the early 20th century, renovations were made to the Paddock Building. The arcade received a translucent, steel-and-wire-glass dropped ceiling between its second and third stories, which still allowed light to filter in from its glass roof.