We must keep quiet in the hospital.医院内必须保持安静
We mustn't smoke in the hospital.医院内禁止吸烟还有 We mustn’t____in the hospital、We must___at the museum、We mustn‘t___at the museumWe mustn't smoke in the hospital.医院内禁止吸烟。We mustbeware of pickpockets at the museum.博物馆内小心扒手。We mustn‘ttake photos at the museum.博物馆禁止拍照。We mustn‘ttouch the exhibits/objects.勿触摸博物馆展品。