Complex sentence: Run by Philip Hiss and H. Hobart Weekes, the firm was known primarily for the hotels and apartment buildings they built in Manhattan and the summer residences they built for wealthy city dwellers on the Gold Coast of Long Island and in Berkshire County, Massachusetts.
Split into simpler sentences: Run by Philip Hiss and H. Hobart Weekes, the firm was known primarily for the hotels and apartment buildings they built in Manhattan. They also built summer residences for wealthy city dwellers on the Gold Coast of Long Island and in Berkshire County, Massachusetts.