阅读下列古诗，完成问题。
                                                                                                         （四）登高
                                                                                                                    杜甫
                                                                                          风急天高猿啸哀，渚清沙白鸟飞回。
                                                                                          无边落木萧萧下，不尽长江滚滚来。
                                                                                          万里悲秋常作客，百年多病独登台。
                                                                                          艰难苦恨繁霜鬓，潦倒新停浊酒杯。