古诗鉴赏，回答相关问题。
                                                                                                                次北固山下（王湾）
                                                                              客路青山外，行舟绿水前。潮平两岸阔，风正一帆悬。
                                                                              海日生残夜，江春入旧年。乡书何处达，归雁洛阳边。