off duty. According to the official website of Qingdao Zhanqiao Prince Hotel, as of May, 2123, Qingdao Zhanqiao Prince Hotel still provides accommodation and catering services, which is in a normal business state and still open, so it can only be closed. Trestle, a bridge-like building, a station, a port, a mine or a factory, is a temporary bridge structure used for loading and unloading goods or getting on and off passengers, or for traffic, mechanical arrangement and aerial work on the construction site.