给以下句子添加标点符号、大小写和适当的换行，并将其输出为一篇可读性良好的段落。 "in the heart of my country lies a beautiful city it is surrounded by mountains and has a river flowing through it the people are friendly and the food is delicious"
In the heart of my country lies a beautiful city. It is surrounded by mountains and has a river flowing through it. The people are friendly and the food is delicious.