[问答题]

珠江是华南一大河系，流经广州市，是中国第三长的河流，仅次于长江和黄河。珠江三角洲(delta)是中国最发达的地区之一，面积约11000平方公里。它在面积和人口方面也是世界上最大的城市聚集区。珠江三角洲九个最大城市共有5700多万人口。上世纪70年代末中国改革开放以来，珠江三角洲已成为中国和世界主要经济区域和制造中心之一。

　　The Pearl River, one of the largest river systems in southern China, runs through Guangzhou city. It is the third longest river in China, only after the Yangtze River and the Yellow River. The Pearl River delta is one of the most advanced regions in China. It is blessed with an area of about 11,000 square kilometers. The delta is the largest urban gathering area worldwide in terms of size and population. The nine largest cities here are home to a combined population of more than 57 million. Ever since the reform and opening up policy was implemented by the Chinese government in the late 1970s, the Pearl River delta has emerged as one of the major economic zones and leading manufacturing centers of China and the world.