First write the poet's dilemma of staying in Jianghan in a self-deprecating way. "Homesickness" means that the poet wants to return to his hometown but can't, so he has to wander around and wander around the world. Contains the poet's infinite bitterness.
The second link is the description of the natural scenery in front of us. Literally, the poet sees a lonely moon, but in fact, they are used as metaphors of the poet himself. The poet integrates his inner feelings into the external scenery, feeling that although he is wandering around, his loyalty to the country is still as bright as a lonely moon.
The third part uses metaphor to write the poet's mental state in adversity. "Sunset" is the antonym of "autumn wind". The former is imaginary writing, which is a metaphor for "twilight", while the latter is real writing. Being in Jianghan, facing the autumn wind, the poet not only lost his sentimental feelings in the past, but also felt "sick for Sue". This change is the embodiment of the poet's heroic mentality and active spirit of using the world.
Wei Lian borrowed an allusion from an old horse who knew the way. The poet compares himself to an "old horse" to show that he is not worthless. Although he is old and ill, he still has wisdom to use and can still make a difference.
The whole poem uses euphemistic and implicit techniques, which fully shows the poet's psychological state of being strong and brave.
The above is from Baidu Encyclopedia.