What kind of emotion does the jagged dance of residual willows express?

Nostalgia is the pain of today. "Irregular Dance of Residual Willow", Liu Ben is delicate and rotten as residual, so his dance is also uneven, but he still dances endlessly. The word "dance" is persistent and powerful, with desolation in it and desolation in it. In fact, the natural image of "the dancing of residual willows" is a symbol of the decline of the Southern Song Dynasty, implying that although it is broken, it is unwilling to perish. This is similar to Li Shangyin's "Leyou Tombs" and "to see the sun, for all his glory, Buried by the Coming Night", which symbolizes the irretrievability of the national fortune in the Tang Dynasty. As a natural image itself, it complements the natural meaning of "what is the present".

Therefore, this sentence shows the author's concern for the country and his sadness and unwillingness to decline in the Southern Song Dynasty.