I was doing a translation on an A2 practice sheet and the phrase: "Decorated trees and pretty candles could be seen in windows everywhere" was translated to "Geschmuectkte Baeume und huebsche Kerzen waren ueberall in den Fenstern zu sehen." I was wondering how waren...zu sehen can be translated so that konnten doesn't need to be used. My guess is that waren...zu sehen could be translated as "were to be seen". Is this a passive construction? And if so, why does it not use wurden instead of waren? Any insight would be much appreciated.