Complex sentence: The early 1990s were also many hotels, guest houses and apartments, shops have been restored in the city center and built a marina with 400 berths and 200 apartments in the vicinity of the Szczecin Lagoon.
Split into simpler sentences: The early 1990s also saw the restoration of many hotels, guest houses, apartments, and shops in the city center. A marina with 400 berths and 200 apartments was built in the vicinity of the Szczecin Lagoon.