(1) is not a common view. Hu Ceng, a contemporary poet of Pi Rixiu, commented on the Grand Canal in a completely opposite way, which can only represent Pi Rixiu's personal views. Pi Rixiu lived in the late Tang Dynasty, especially after the Huang Chao Uprising. The central military and political power was completely lost, and decrees were not allowed to go through the customs. The author is very worried about the present situation of the country, and uses this poem to warn the rulers of later generations that glory and extinction often happen in an instant.

(2) The author's understanding is not very profound, but only superficial. The achievements of the Grand Canal are the benefits brought to future generations, and "up to now" particularly emphasizes the long-term benefits. "There is no water in the temple, the dragon boat incident" seems to be to protect Yang Di, but in fact, the author did not see Yang Guang's real intention of digging the Grand Canal. Scholars' views are often in sharp contrast, with clear love and hate, but the farther away from historical facts.