Oranges born in Huainan are oranges, and oranges born in Huaibei are oranges. That is to say, oranges grown in the south of Huaihe River are delicious oranges, while oranges grown in the north of Huaihe River are inedible oranges.

This sentence comes from Liu Xiang's Yanzi Chunqiu, which means: the dried tangerine peel south of Huaihe River grows into dried tangerine peel, and the north of Huaihe River becomes a bitter tree.

The difference between them lies in the different growing environment, which leads to oranges in the south and oranges in the north.