This sentence comes from the children's song "Waipoqiao", which describes the snacks sold on Waipoqiao. The whole sentence means: "There are jiaozi and cakes in a bag of sugar", which means there are vendors selling sugar and fruits, and there are also stalls selling jiaozi and cakes. This sentence vividly depicts the lively scene on the Waipo Bridge through simple and clear expression, leaving a good impression on people.